[PATCH v2][Binutils] arm: Add supprot for Armv8.9-A and Armv9.4-A.

[Nick Clifton]

Hi Srinath,

> This patch adds AArch32 support for -march=armv8.9-a and
> -march=armv9.4-a. The behaviour of the new options can be
> expressed using a combination of existing feature flags
> and tables.
> 
> The cpu_arch_ver entries for ARM_ARCH_V9_4A and ARM_ARCH_V8_9A
> are technically redundant but it including them for macro code
> consistency across architectures.
> 
> Regression testing for arm-none-eabi target and found
> no regressions.
> 
> Ok for binutils-master?

Approved - please apply.

Cheers
   Nick