fix(cpus): workaround for Cortex-A715 erratum 2728106

Cortex-A715 erratum 2728106 is a Cat B(rare) erratum that is present
in revision r0p0, r1p0 and r1p1. It is fixed in r1p2.

The workaround is to execute an implementation specific sequence in
the CPU.

SDEN documentation:
https://developer.arm.com/documentation/SDEN2148827/latest

Change-Id: Ic825f9942e7eb13893fdbb44a2090b897758cbc4
Signed-off-by: Bipin Ravi <bipin.ravi@arm.com>
3 files changed