amdgcn: Add -mxnack and -msram-ecc [PR 100208]

amdgcn: Add -mxnack and -msram-ecc [PR 100208]

gcc/ChangeLog:

	PR target/100208
	* config/gcn/gcn-hsa.h (DRIVER_SELF_SPECS): New.
	(ASM_SPEC): Set -mattr for xnack and sram-ecc.
	* config/gcn/gcn-opts.h (enum sram_ecc_type): New.
	* config/gcn/gcn-valu.md: Add a warning comment.
	* config/gcn/gcn.c (gcn_option_override): Add "sorry" for -mxnack.
	(output_file_start): Add xnack and sram-ecc state to ".amdgcn_target".
	* config/gcn/gcn.md: Add a warning comment.
	* config/gcn/gcn.opt: Add -mxnack and -msram-ecc.
	* config/gcn/mkoffload.c (EF_AMDGPU_MACH_AMDGCN_GFX908): Remove
	SRAM-ECC flag.
	(EF_AMDGPU_XNACK): New.
	(EF_AMDGPU_SRAM_ECC): New.
	(elf_flags): New.
	(copy_early_debug_info): Use elf_flags.
	(main): Handle -mxnack and -msram-ecc options.
	* doc/invoke.texi: Document -mxnack and -msram-ecc.

gcc/testsuite/ChangeLog:

	PR target/100208
	* gcc.target/gcn/sram-ecc-1.c: New test.
	* gcc.target/gcn/sram-ecc-2.c: New test.
	* gcc.target/gcn/sram-ecc-3.c: New test.
	* gcc.target/gcn/sram-ecc-4.c: New test.
	* gcc.target/gcn/sram-ecc-5.c: New test.
	* gcc.target/gcn/sram-ecc-6.c: New test.
	* gcc.target/gcn/sram-ecc-7.c: New test.
	* gcc.target/gcn/sram-ecc-8.c: New test.

(cherry picked from commit aad32a00b7d2b64ae158b2b167768a9ae3e20f6e)