Add output_type to bfd_link_info

Add output_type to bfd_link_info

The "shared" field in bfd_link_info is set for both DSO and and PIE.
There are separate fields for executable and relocatable outputs.  This
patch adds an "output_type" field:

enum output_type
{
  type_unknown = 0,
  type_executable,
  type_dll,
  type_relocatable
};

and a "pic" field to bfd_link_info to replace shared, executable and
relocatable fields so that we can use the "output_type" field to check
for output type and the "pic" field check if output is PIC.  Macros,
bfd_link_executable, bfd_link_dll, bfd_link_relocatable, bfd_link_pic
and bfd_link_pie, are provided to check for output features.

bfd/

	* bfd/aoutx.h: Replace shared, executable, relocatable and pie
	fields with bfd_link_executable, bfd_link_dll,
	bfd_link_relocatable, bfd_link_pic and bfd_link_pie.
	* bfd/bout.c: Likewise.
	* bfd/coff-alpha.c: Likewise.
	* bfd/coff-arm.c: Likewise.
	* bfd/coff-i386.c: Likewise.
	* bfd/coff-i960.c: Likewise.
	* bfd/coff-m68k.c: Likewise.
	* bfd/coff-mcore.c: Likewise.
	* bfd/coff-mips.c: Likewise.
	* bfd/coff-ppc.c: Likewise.
	* bfd/coff-rs6000.c: Likewise.
	* bfd/coff-sh.c: Likewise.
	* bfd/coff-tic80.c: Likewise.
	* bfd/coff-x86_64.c: Likewise.
	* bfd/coff64-rs6000.c: Likewise.
	* bfd/coffgen.c: Likewise.
	* bfd/cofflink.c: Likewise.
	* bfd/ecoff.c: Likewise.
	* bfd/ecofflink.c: Likewise.
	* bfd/elf-bfd.h: Likewise.
	* bfd/elf-eh-frame.c: Likewise.
	* bfd/elf-ifunc.c: Likewise.
	* bfd/elf-m10200.c: Likewise.
	* bfd/elf-m10300.c: Likewise.
	* bfd/elf-s390-common.c: Likewise.
	* bfd/elf-vxworks.c: Likewise.
	* bfd/elf.c: Likewise.
	* bfd/elf32-arm.c: Likewise.
	* bfd/elf32-avr.c: Likewise.
	* bfd/elf32-bfin.c: Likewise.
	* bfd/elf32-cr16.c: Likewise.
	* bfd/elf32-cr16c.c: Likewise.
	* bfd/elf32-cris.c: Likewise.
	* bfd/elf32-crx.c: Likewise.
	* bfd/elf32-d10v.c: Likewise.
	* bfd/elf32-dlx.c: Likewise.
	* bfd/elf32-epiphany.c: Likewise.
	* bfd/elf32-fr30.c: Likewise.
	* bfd/elf32-frv.c: Likewise.
	* bfd/elf32-ft32.c: Likewise.
	* bfd/elf32-h8300.c: Likewise.
	* bfd/elf32-hppa.c: Likewise.
	* bfd/elf32-i370.c: Likewise.
	* bfd/elf32-i386.c: Likewise.
	* bfd/elf32-i860.c: Likewise.
	* bfd/elf32-ip2k.c: Likewise.
	* bfd/elf32-iq2000.c: Likewise.
	* bfd/elf32-lm32.c: Likewise.
	* bfd/elf32-m32c.c: Likewise.
	* bfd/elf32-m32r.c: Likewise.
	* bfd/elf32-m68hc11.c: Likewise.
	* bfd/elf32-m68hc1x.c: Likewise.
	* bfd/elf32-m68k.c: Likewise.
	* bfd/elf32-mcore.c: Likewise.
	* bfd/elf32-mep.c: Likewise.
	* bfd/elf32-metag.c: Likewise.
	* bfd/elf32-microblaze.c: Likewise.
	* bfd/elf32-moxie.c: Likewise.
	* bfd/elf32-msp430.c: Likewise.
	* bfd/elf32-mt.c: Likewise.
	* bfd/elf32-nds32.c: Likewise.
	* bfd/elf32-nios2.c: Likewise.
	* bfd/elf32-or1k.c: Likewise.
	* bfd/elf32-ppc.c: Likewise.
	* bfd/elf32-rl78.c: Likewise.
	* bfd/elf32-rx.c: Likewise.
	* bfd/elf32-s390.c: Likewise.
	* bfd/elf32-score.c: Likewise.
	* bfd/elf32-score7.c: Likewise.
	* bfd/elf32-sh-symbian.c: Likewise.
	* bfd/elf32-sh.c: Likewise.
	* bfd/elf32-sh64.c: Likewise.
	* bfd/elf32-spu.c: Likewise.
	* bfd/elf32-tic6x.c: Likewise.
	* bfd/elf32-tilepro.c: Likewise.
	* bfd/elf32-v850.c: Likewise.
	* bfd/elf32-vax.c: Likewise.
	* bfd/elf32-visium.c: Likewise.
	* bfd/elf32-xc16x.c: Likewise.
	* bfd/elf32-xstormy16.c: Likewise.
	* bfd/elf32-xtensa.c: Likewise.
	* bfd/elf64-alpha.c: Likewise.
	* bfd/elf64-hppa.c: Likewise.
	* bfd/elf64-ia64-vms.c: Likewise.
	* bfd/elf64-mmix.c: Likewise.
	* bfd/elf64-ppc.c: Likewise.
	* bfd/elf64-s390.c: Likewise.
	* bfd/elf64-sh64.c: Likewise.
	* bfd/elf64-x86-64.c: Likewise.
	* bfd/elflink.c: Likewise.
	* bfd/elfnn-aarch64.c: Likewise.
	* bfd/elfnn-ia64.c: Likewise.
	* bfd/elfxx-mips.c: Likewise.
	* bfd/elfxx-sparc.c: Likewise.
	* bfd/elfxx-tilegx.c: Likewise.
	* bfd/i386linux.c: Likewise.
	* bfd/linker.c: Likewise.
	* bfd/m68klinux.c: Likewise.
	* bfd/pdp11.c: Likewise.
	* bfd/pe-mips.c: Likewise.
	* bfd/peXXigen.c: Likewise.
	* bfd/reloc.c: Likewise.
	* bfd/reloc16.c: Likewise.
	* bfd/sparclinux.c: Likewise.
	* bfd/sunos.c: Likewise.
	* bfd/vms-alpha.c: Likewise.
	* bfd/xcofflink.c: Likewise.

include/

	* include/bfdlink.h (output_type): New enum.
	(bfd_link_executable): New macro.
	(bfd_link_dll): Likewise.
	(bfd_link_relocatable): Likewise.
	(bfd_link_pic): Likewise.
	(bfd_link_pie): Likewise.
	(bfd_link_info): Remove shared, executable, pie and relocatable.
	Add output_type and pic.

ld/

	* ld/ldctor.c: Replace shared, executable, relocatable and pie
	fields with bfd_link_executable, bfd_link_dll,
	bfd_link_relocatable, bfd_link_pic and bfd_link_pie.
	* ld/ldemul.c: Likewise.
	* ld/ldfile.c: Likewise.
	* ld/ldlang.c: Likewise.
	* ld/ldmain.c: Likewise.
	* ld/ldwrite.c: Likewise.
	* ld/lexsup.c: Likewise.
	* ld/pe-dll.c: Likewise.
	* ld/plugin.c: Likewise.
	* ld/emultempl/aarch64elf.em: Likewise.
	* ld/emultempl/aix.em: Likewise.
	* ld/emultempl/alphaelf.em: Likewise.
	* ld/emultempl/armcoff.em: Likewise.
	* ld/emultempl/armelf.em: Likewise.
	* ld/emultempl/avrelf.em: Likewise.
	* ld/emultempl/beos.em: Likewise.
	* ld/emultempl/cr16elf.em: Likewise.
	* ld/emultempl/elf-generic.em: Likewise.
	* ld/emultempl/elf32.em: Likewise.
	* ld/emultempl/genelf.em: Likewise.
	* ld/emultempl/generic.em: Likewise.
	* ld/emultempl/gld960.em: Likewise.
	* ld/emultempl/gld960c.em: Likewise.
	* ld/emultempl/hppaelf.em: Likewise.
	* ld/emultempl/irix.em: Likewise.
	* ld/emultempl/linux.em: Likewise.
	* ld/emultempl/lnk960.em: Likewise.
	* ld/emultempl/m68hc1xelf.em: Likewise.
	* ld/emultempl/m68kcoff.em: Likewise.
	* ld/emultempl/m68kelf.em: Likewise.
	* ld/emultempl/metagelf.em: Likewise.
	* ld/emultempl/mipself.em: Likewise.
	* ld/emultempl/mmo.em: Likewise.
	* ld/emultempl/msp430.em: Likewise.
	* ld/emultempl/nds32elf.em: Likewise.
	* ld/emultempl/needrelax.em: Likewise.
	* ld/emultempl/nios2elf.em: Likewise.
	* ld/emultempl/pe.em: Likewise.
	* ld/emultempl/pep.em: Likewise.
	* ld/emultempl/ppc32elf.em: Likewise.
	* ld/emultempl/ppc64elf.em: Likewise.
	* ld/emultempl/sh64elf.em: Likewise.
	* ld/emultempl/solaris2.em: Likewise.
	* ld/emultempl/spuelf.em: Likewise.
	* ld/emultempl/sunos.em: Likewise.
	* ld/emultempl/tic6xdsbt.em: Likewise.
	* ld/emultempl/ticoff.em: Likewise.
	* ld/emultempl/v850elf.em: Likewise.
	* ld/emultempl/vms.em: Likewise.
	* ld/emultempl/vxworks.em: Likewise.