[PATCH][GAS] aarch64: Add WFET instruction for Armv8.7-a

[Nick Clifton]

Hi Przemyslaw,

> gas/ChangeLog:
> 
> 2020-10-27  Przemyslaw Wirkus  <przemyslaw.wirkus@arm.com>
> 
> 	* NEWS: Update docs.
> 	* testsuite/gas/aarch64/system-5.d: New test.
> 	* testsuite/gas/aarch64/system-5.s: New test.
> 
> opcodes/ChangeLog:
> 
> 2020-10-27  Przemyslaw Wirkus  <przemyslaw.wirkus@arm.com>
> 
> 	* aarch64-tbl.h (struct aarch64_opcode): Add new WFET instruction encoding
> 	and operand description.
> 	* aarch64-asm-2.c: Regenerate.
> 	* aarch64-dis-2.c: Regenerate.
> 	* aarch64-opc-2.c: Regenerate.

Approved - please apply.

Cheers
  Nick