arch-arm: Add support for Armv8.2-I8MM NEON extension.

Add support for the Armv8.2-I8MM NEON extension. This provides the
SUDOT and USDOT mixed-sign SIMD Dot Product instructions, as well as
the SMMLA, UMMLA, and USMMLA SIMD Matrix Multiply-Accumulate
instructions.

For more information please refer to the Arm Architecture Reference
Manual (https://developer.arm.com/documentation/ddi0487/latest/).

Additional Contributors: Giacomo Travaglini

Change-Id: I6fb9318f67cc9d2737079283e1a095630c4d2ad9
Reviewed-by: Richard Cooper <richard.cooper@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/70737
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
5 files changed