[GAS][ARM] Add support for Cortex-A78 and Cortex-A78AE

[Nick Clifton]

Hi Przemyslaw,

> OK for master branch ?

Approved.

> PS: I do not have write permission, can this be commited in my name if
> approved please?

With luck you will soon have access, so please apply this patch as a test
of that access.

Cheers
  Nick

> bfd/ChangeLog:
> 2020-09-30  Przemyslaw Wirkus  <przemyslaw.wirkus@arm.com>
> 
> 	* cpu-arm.c: Add cortex-a78 and cortex-a78ae.
> 
> gas/ChangeLog:
> 2020-09-30  Przemyslaw Wirkus  <przemyslaw.wirkus@arm.com>
> 
> 	* config/tc-arm.c: Add cortex-a78 and cortex-a78ae cores.
> 	* doc/c-arm.texi: Update docs.
> 	* NEWS: Update news.
> 	* testsuite/gas/arm/cpu-cortex-a78.d: New test.
> 	* testsuite/gas/arm/cpu-cortex-a78ae.d: New test.