linux64.h: Delete file.

linux64.h: Delete file.

	* config/s390/linux64.h: Delete file.
	* config/s390/s390x.h: New file.
	* config.gcc (s390x-*-linux*): Use s390x.h instead of linux64.h
	as target header file.
	* config/s390/linux.h (TARGET_VERSION): Define depending on
	DEFAULT_TARGET_64BIT.
	(CPP_SPEC, ASM_SPEC, LINK_SPEC): Likewise.
	(SIZE_TYPE, PTRDIFF_TYPE): Likewise.
	(NO_BUILTIN_SIZE_TYPE, NO_BUILTIN_PTRDIFF_TYPE): Define.
	(CPP_ARCH31_SPEC, CPP_ARCH64_SPEC): New defines.
	(LINK_ARCH31_SPEC, LINK_ARCH64_SPEC): New defines.
	(EXTRA_SPEC): New define.
	* config/s390/s390.h (TARGET_VERSION): Define depending on
	DEFAULT_TARGET_64BIT.
	(MASK_RETURN_ADDR): Add run-time check for TARGET_64BIT.

From-SVN: r49552