fix(errata): workaround for Neoverse-N2 erratum 2242415

Neoverse-N2 erratum 2242415 is a Cat B erratum that applies to
revision r0p0 of CPU. It is still open. The workaround
is to set CPUACTLR_EL1[22] to 1'b1. Setting CPUACTLR_EL1[22]
will cause CFP instruction to invalidate all branch predictor
resources regardless of context.

SDEN can be found here:
https://developer.arm.com/documentation/SDEN1982442/latest

Signed-off-by: nayanpatel-arm <nayankumar.patel@arm.com>
Change-Id: I442be81fbc32e21fed51a84f59584df17f845e96
4 files changed