[AArch64][PATCH 2/2] Support ARMv8.2 DC CVAP instruction.

[AArch64][PATCH 2/2] Support ARMv8.2 DC CVAP instruction.

ARMv8.2 adds the new system instruction DC CVAP. This patch adds support
for the instruction to binutils, enabled when -march=armv8.2-a is
selected.

gas/
2015-12-10  Matthew Wahab  <matthew.wahab@arm.com>

	* config/tc-aarch64.c (parse_sys_ins_reg): Add check of
	architectural support for system register.

gas/testsuite/
2015-12-10  Matthew Wahab  <matthew.wahab@arm.com>

	* gas/aarch64/sysreg-2.d: Add tests for dc instruction.
	* gas/aarch64/sysreg-2.s: Add uses of dc instruction.

include/opcode/
2015-12-10  Matthew Wahab  <matthew.wahab@arm.com>

	* aarch64.h (aarch64_sys_ins_reg_supported_p): Declare.

opcodes/
2015-12-10  Matthew Wahab  <matthew.wahab@arm.com>

	* aarch64-opc.c (aarch64_sys_regs_dc): Add "cvap".
	(aarch64_sys_ins_reg_supported_p): New.

Change-Id: I3158b97d9bbee9644c2d0e2986db807412ef1053