gcconfig.h (AARCH64): New macro (defined only if __aarch64__).

gcconfig.h (AARCH64): New macro (defined only if __aarch64__).

2013-03-16  Yvan Roux <yvan.roux@linaro.org>

        * include/private/gcconfig.h (AARCH64): New macro (defined only if
	__aarch64__).
	* include/private/gcconfig.h (mach_type_known):
	Update comment adding ARM AArch64 target.
	* include/private/gcconfig.h (NOSYS, mach_type_known,CPP_WORDSZ,
	MACH_TYPE, ALIGNMENT, HBLKSIZE, OS_TYPE, LINUX_STACKBOTTOM,
	USE_GENERIC_PUSH_REGS, DYNAMIC_LOADING, DATASTART, DATAEND,
	STACKBOTTOM): Define for AArch64.

From-SVN: r197770