fix(cpus): add erratum 2701951 to Cortex-X3's list

Erratum ID 2701951 is an erratum that could affect platforms that
do not use an Arm interconnect IP. This was originally added to the list
of Cortex-A715 in the errata ABI files.
Fixed this by adding it to the Cortex-X3 list.

SDEN documentation:
https://developer.arm.com/documentation/2055130/latest



Change-Id: I6ffaf4360a4a2d0a23c253a2326c178e010c8e45
Signed-off-by: Sona Mathew <sonarebecca.mathew@arm.com>