Enhance GAS's .section directive so that it can take numeric values for the flags...

Enhance GAS's .section directive so that it can take numeric values for the flags and type fields.  (ELF only)

gas	* doc/as.texinfo (.section): Document that numeric values can now
	be used for the flags and type fields of the ELF target's .section
	directive.  Add notes about the restrictions on setting flags and
	types.
	* config/obj-elf.c (obj_elf_change_section): Allow known sections
	to be given processor specific section types.  Allow processor and
	application specific flags of a section to be set after
	definition.
	(obj_elf_parse_section_letters): Handle parsing numeric values.
	(obj_elf_section_type): Handle parsing numeric values.
	(obj_elf_section): Allow numeric type values.
	* config/obj-elf.h (obj_elf_change_section): Update prototype.
	* testsuite/gas/elf/section10.d: New test.
	* testsuite/gas/elf/section10.s: Source file for new test.
	* testsuite/gas/elf/elf.exp: Run the new test.
	* testsuite/gas/i386/ilp32/x86-64-unwind.d: Remove dependency upon
	the description of the flags produced by readelf.
	* testsuite/gas/tic6x/scomm-directive-4.d: Likewise.
	* NEWS: Mention the new feature.

bfd	* elf-bfd.h (struct bfd_elf_special_section): Use unsigned values
	for length and type fields.  Use a signed value for the
	suffix_length field.

binutils* readelf.c (get_section_type_name): Add hex prefix to offsets
	printed for LOPROC and LOOS values.  Ensure that a result is
	always returned for the V850 target, even when an unrecognised
	processor specific value is encountered.
	(process_section_headers): Display key values in the order in
	which they appear to the user.  Add the "C (compressed)" value to
	the list.

ld	* testsuite/ld-i386/pr12718.d: Remove dependency upon the
	description of the flags produced by readelf.
	* testsuite/ld-i386/pr12921.d: Likewise.
	* testsuite/ld-i386/tlsbin-nacl.rd: Likewise.
	* testsuite/ld-i386/tlsbin.rd: Likewise.
	* testsuite/ld-i386/tlsbindesc-nacl.rd: Likewise.
	* testsuite/ld-i386/tlsbindesc.rd: Likewise.
	* testsuite/ld-i386/tlsdesc-nacl.rd: Likewise.
	* testsuite/ld-i386/tlsdesc.rd: Likewise.
	* testsuite/ld-i386/tlsgdesc-nacl.rd: Likewise.
	* testsuite/ld-i386/tlsgdesc.rd: Likewise.
	* testsuite/ld-i386/tlsnopic-nacl.rd: Likewise.
	* testsuite/ld-i386/tlsnopic.rd: Likewise.
	* testsuite/ld-i386/tlspic-nacl.rd: Likewise.
	* testsuite/ld-i386/tlspic.rd: Likewise.
	* testsuite/ld-s390/tlsbin.rd: Likewise.
	* testsuite/ld-s390/tlsbin_64.rd: Likewise.
	* testsuite/ld-s390/tlspic.rd: Likewise.
	* testsuite/ld-s390/tlspic_64.rd: Likewise.
	* testsuite/ld-sh/tlsbin-2.d: Likewise.
	* testsuite/ld-sh/tlspic-2.d: Likewise.
	* testsuite/ld-tic6x/common.d: Likewise.
	* testsuite/ld-tic6x/shlib-1.rd: Likewise.
	* testsuite/ld-tic6x/shlib-1b.rd: Likewise.
	* testsuite/ld-tic6x/shlib-1r.rd: Likewise.
	* testsuite/ld-tic6x/shlib-1rb.rd: Likewise.
	* testsuite/ld-tic6x/shlib-app-1.rd: Likewise.
	* testsuite/ld-tic6x/shlib-app-1b.rd: Likewise.
	* testsuite/ld-tic6x/shlib-app-1r.rd: Likewise.
	* testsuite/ld-tic6x/shlib-app-1rb.rd: Likewise.
	* testsuite/ld-tic6x/shlib-noindex.rd: Likewise.
	* testsuite/ld-tic6x/static-app-1.rd: Likewise.
	* testsuite/ld-tic6x/static-app-1b.rd: Likewise.
	* testsuite/ld-tic6x/static-app-1r.rd: Likewise.
	* testsuite/ld-tic6x/static-app-1rb.rd: Likewise.
	* testsuite/ld-x86-64/ilp32-4-nacl.d: Likewise.
	* testsuite/ld-x86-64/ilp32-4.d: Likewise.
	* testsuite/ld-x86-64/pr12718.d: Likewise.
	* testsuite/ld-x86-64/pr12921.d: Likewise.
	* testsuite/ld-x86-64/split-by-file-nacl.rd: Likewise.
	* testsuite/ld-x86-64/split-by-file.rd: Likewise.
	* testsuite/ld-x86-64/tlsbin-nacl.rd: Likewise.
	* testsuite/ld-x86-64/tlsbin.rd: Likewise.
	* testsuite/ld-x86-64/tlsbindesc-nacl.rd: Likewise.
	* testsuite/ld-x86-64/tlsbindesc.rd: Likewise.
	* testsuite/ld-x86-64/tlsdesc-nacl.rd: Likewise.
	* testsuite/ld-x86-64/tlsdesc.rd: Likewise.
	* testsuite/ld-x86-64/tlsgdesc-nacl.rd: Likewise.
	* testsuite/ld-x86-64/tlsgdesc.rd: Likewise.
	* testsuite/ld-x86-64/tlspic-nacl.rd: Likewise.
	* testsuite/ld-x86-64/tlspic.rd: Likewise.
	* testsuite/ld-xtensa/tlsbin.rd: Likewise.
	* testsuite/ld-xtensa/tlspic.rd: Likewise.