Pass ignored unresolved relocations to ld backend

Pass ignored unresolved relocations to ld backend

bfd/

	PR ld/4409
	* elf-bfd.h (RELOC_FOR_GLOBAL_SYMBOL): Add an argument for
	error ignored.
	* elf-m10200.c (mn10200_elf_relocate_section): Updated.
	* elf-m10300.c (mn10300_elf_relocate_section): Likewise.
	* elf32-arm.c (elf32_arm_relocate_section): Likewise.
	* elf32-avr.c (elf32_avr_relocate_section): Likewise.
	* elf32-bfin.c (bfinfdpic_relocate_section): Likewise.
	(bfin_relocate_section): Likewise.
	* elf32-cr16.c (elf32_cr16_relocate_section): Likewise.
	* elf32-cr16c.c (elf32_cr16c_relocate_section): Likewise.
	* elf32-cris.c (cris_elf_relocate_section): Likewise.
	* elf32-crx.c (elf32_crx_relocate_section): Likewise.
	* elf32-d10v.c (elf32_d10v_relocate_section): Likewise.
	* elf32-epiphany.c (epiphany_elf_relocate_section): Likewise.
	* elf32-fr30.c (fr30_elf_relocate_section): Likewise.
	* elf32-frv.c (elf32_frv_relocate_section): Likewise.
	* elf32-h8300.c (elf32_h8_relocate_section): Likewise.
	* elf32-hppa.c (elf32_hppa_relocate_section): Likewise.
	* elf32-i386.c (elf_i386_relocate_section): Likewise.
	* elf32-i860.c (elf32_i860_relocate_section): Likewise.
	* elf32-ip2k.c (ip2k_elf_relocate_section): Likewise.
	* elf32-iq2000.c (iq2000_elf_relocate_section): Likewise.
	* elf32-lm32.c (lm32_elf_relocate_section): Likewise.
	* elf32-m68hc1x.c (elf32_m68hc11_relocate_section): Likewise.
	* elf32-m68k.c (elf_m68k_relocate_section): Likewise.
	* elf32-metag.c (elf_metag_relocate_section): Likewise.
	* elf32-microblaze.c (microblaze_elf_relocate_section): Likewise.
	* elf32-mcore.c (mcore_elf_relocate_section): Likewise.
	* elf32-mep.c (mep_elf_relocate_section): Likewise.
	* elf32-moxie.c (moxie_elf_relocate_section): Likewise.
	* elf32-msp430.c (elf32_msp430_relocate_section): Likewise.
	* elf32-mt.c (mt_elf_relocate_section): Likewise.
	* elf32-nios2.c (nios2_elf32_relocate_section): Likewise.
	* elf32-openrisc.c (openrisc_elf_relocate_section): Likewise.
	* elf32-ppc.c (ppc_elf_relocate_section): Likewise.
	* elf32-rl78.c (rl78_elf_relocate_section): Likewise.
	* elf32-rx.c (rx_elf_relocate_section): Likewise.
	* elf32-tic6x.c (elf32_tic6x_relocate_section): Likewise.
	* elf32-tilepro.c (tilepro_elf_relocate_section): Likewise.
	* elf32-s390.c (elf_s390_relocate_section): Likewise.
	* elf32-v850.c (v850_elf_relocate_section): Likewise.
	* elf32-vax.c (elf_vax_relocate_section): Likewise.
	* elf32-xc16x.c (elf32_xc16x_relocate_section): Likewise.
	* elf32-xstormy16.c (xstormy16_elf_relocate_section): Likewise.
	* elf32-xtensa.c (elf_xtensa_relocate_section): Likewise.
	* elf64-alpha.c (elf64_alpha_relocate_section): Likewise.
	* elf64-ia64-vms.c (elf64_ia64_relocate_section): Likewise.
	* elf64-mmix.c (mmix_elf_relocate_section): Likewise.
	* elf64-ppc.c (ppc64_elf_relocate_section): Likewise.
	* elf64-s390.c (elf_s390_relocate_section): Likewise.
	* elf64-x86-64.c (elf64_x86_64_relocate_section): Likewise.
	* elfxx-sparc.c (_bfd_sparc_elf_relocate_section): Likewise.
	* elfxx-tilegx.c (tilegx_elf_relocate_section): Likewise.
	* elfnn-aarch64.c (elfNN_aarch64_relocate_section): Likewise.

	* elfnn-ia64.c (elfNN_ia64_relocate_section): Skip if error
	from RELOC_FOR_GLOBAL_SYMBOL in executable is ignored.

ld/testsuite/

	PR ld/4409
	* ld-ia64/error1.d: New file.
	* ld-ia64/error1.s: Likewise.
	* ld-ia64/error2.d: Likewise.
	* ld-ia64/error3.d: Likewise.