[ARM] Support for ARMv8.1 command line option

[ARM] Support for ARMv8.1 command line option

2015-06-03  Matthew Wahab  <matthew.wahab@arm.com>

gas/
	* config/tc-arm.c (arm_archs): Add "armv8.1-a".
	* doc/c-arm.texi (ARM Options, -march): Add "armv8.1-a".
	* NEWS: Mention ARMv8.1 support.

include/opcode/
	* arm.h (FPU_ARCH_CRYPTO_NEON_VFP_ARMV8_1): New.
	(ARM_ARCH_V8_1A): New.
	(ARM_ARCH_V8_1A_FP): New.
	(ARM_ARCH_V8_1A_SIMD): New.
	(ARM_ARCH_V8_1A_CRYPTOV1): New.
	(ARM_FEATURE_CORE): New.