[PATCH 2/2][Aarch64][gas] Add support for PAN architecture extension.

[Nicholas Clifton]

Hi Matthew,

> gas/
> 2015-05-20  Matthew Wahab  <matthew.wahab@arm.com>
>
>      * config/tc-aarch64.c (parse_sys_reg): New parameter.  Check
>      target support.  Fix whitespace.
>      (parse_operands): Update for parse_sys_reg changes.
>      (aarch64_features): Add "pan".
>      * doc/c-aarch64.texi (Aarch64 Extensions): Add "pan".
>
> gas/testsuite
> 2015-05-20  Matthew Wahab  <matthew.wahab@arm.com>
>
>      * pan-directive.d: New.
>      * pan.d: New.
>      * pan.s: New

Approved - please apply.

Cheers
   Nick