[Patch AArch64 2/3] Rework the code to print extension strings (pr70133)

[Patch AArch64 2/3] Rework the code to print extension strings (pr70133)

gcc/

	PR target/70133
	* config/aarch64/aarch64-common.c (aarch64_option_extension): Keep
	track of a canonical flag name.
	(all_extensions): Likewise.
	(arch_to_arch_name): Also track extension flags enabled by the arch.
	(all_architectures): Likewise.
	(aarch64_parse_extension): Move to here.
	(aarch64_get_extension_string_for_isa_flags): Take a new argument,
	rework.
	(aarch64_rewrite_selected_cpu): Update for above change.
	* config/aarch64/aarch64-option-extensions.def: Rework the way flags
	are handled, such that the single explicit value enabled by an
	extension is kept seperate from the implicit values it also enables.
	* config/aarch64/aarch64-protos.h (aarch64_parse_opt_result): Move
	to here.
	(aarch64_parse_extension): New.
	* config/aarch64/aarch64.c (aarch64_parse_opt_result): Move from
	here to config/aarch64/aarch64-protos.h.
	(aarch64_parse_extension): Move from here to
	common/config/aarch64/aarch64-common.c.
	(aarch64_option_print): Update.
	(aarch64_declare_function_name): Likewise.
	(aarch64_start_file): Likewise.
	* config/aarch64/driver-aarch64.c (arch_extension): Keep track of
	the canonical flag for extensions.
	* config.gcc (aarch64*-*-*): Extend regex for capturing extension
	flags.

gcc/testsuite/

	PR target/70133
	* gcc.target/aarch64/mgeneral-regs_4.c: Fix expected output.
	* gcc.target/aarch64/target_attr_15.c: Likewise.

From-SVN: r234876