[AArch64][8/14] Implement TARGET_OPTION_VALID_ATTRIBUTE_P

[AArch64][8/14] Implement TARGET_OPTION_VALID_ATTRIBUTE_P

	* common/config/aarch64/aarch64-common.c (aarch64_handle_option):
	Remove static.  Handle OPT_mgeneral_regs_only,
	OPT_mfix_cortex_a53_835769, OPT_mstrict_align,
	OPT_momit_leaf_frame_pointer.
	* config/aarch64/aarch64.c: Include opts.h and diagnostic.h
	(aarch64_attr_opt_type): New enum.
	(aarch64_attribute_info): New struct.
	(aarch64_handle_attr_arch): New function.
	(aarch64_handle_attr_cpu): Likewise.
	(aarch64_handle_attr_tune): Likewise.
	(aarch64_handle_attr_isa_flags): Likewise.
	(aarch64_attributes): New table.
	(aarch64_process_one_target_attr): New function.
	(num_occurences_in_str): Likewise.
	(aarch64_process_target_attr): Likewise.
	(aarch64_option_valid_attribute_p): Likewise.
	(TARGET_OPTION_VALID_ATTRIBUTE_P): Define.
	* config/aarch64/aarch64-protos.h: Include input.h
	(aarch64_handle_option): Declare prototype.

From-SVN: r226560