fix(cpus): workaround for Cortex-A715 erratum 2561034

Cortex-A715 erratum 2561034 is a Cat B erratum that applies to
revision r1p0 and is fixed in r1p1.

The workaround is to set bit[26] in CPUACTLR2_EL1. Setting this
bit is not expected to have a significant performance impact.

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

Change-Id: I377f250a2994b6ced3ac7d93f947af6ceb690d49
Signed-off-by: Bipin Ravi <bipin.ravi@arm.com>
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index 31430ae..dcbeba1 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -903,6 +903,10 @@
 # This erratum applies to revisions r0p0, r0p1. Fixed in r0p2.
 CPU_FLAG_LIST += ERRATA_V2_2801372
 
+# Flag to apply erratum 2561034 workaround during reset. This erratum applies
+# only to revision r1p0. It is fixed in r1p1.
+CPU_FLAG_LIST += ERRATA_A715_2561034
+
 # Flag to apply erratum 2701951 workaround for non-arm interconnect ip.
 # This erratum applies to revisions r0p0, r1p0, and r1p1. Its is fixed in r1p2.
 CPU_FLAG_LIST += ERRATA_A715_2701951