* config.gcc (aarch64*-*-*): Add aarch-common.o to extra_objs.  Add
	aarch-common-protos.h to extra_headers.
	(aarch64*-*-*): Add arm/aarch-common-protos.h to tm_p_file.
	* config/aarch64/aarch64.md: Include "../arm/cortex-a53.md"
	* config/aarch64/t-aarch64 (aarch-common.o): Define.

From-SVN: r201400