fix(errata): workaround for Cortex-A710 erratum 2147715

Cortex-A710 erratum 2147715 is a Cat B erratum that applies
to revision r2p0 of the CPU, and is fixed in r2p1. The work-
around is to set CPUACTLR_EL1[22]=1. Setting this will cause
the CFP instruction to invalidate all branch predictor resources
regardless of the context.

SDEN can be found here:
https://developer.arm.com/documentation/SDEN1775101/latest

Signed-off-by: Akram Ahmad <Akram.Ahmad@arm.com>
Change-Id: I94771bc1fc9b65a0c17d75200ec2b1df8a3279c6
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index 3e5e92a..b382012 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -524,6 +524,10 @@
 # to revision r0p0, r1p0 and r2p0 of the Cortex-A710 cpu and is fixed in r2p1.
 ERRATA_A710_2136059	?=0
 
+# Flag to apply erratum 2147715 workaround during reset. This erratum applies
+# to revision r2p0 of the Cortex-A710 CPU and is fixed in revision r2p1.
+ERRATA_A710_2147715	?=0
+
 # Flag to apply erratum 2282622 workaround during reset. This erratum applies
 # to revision r0p0, r1p0 and r2p0 of the Cortex-A710 cpu and is fixed in r2p1.
 ERRATA_A710_2282622	?=0
@@ -1099,6 +1103,10 @@
 $(eval $(call assert_boolean,ERRATA_A710_2136059))
 $(eval $(call add_define,ERRATA_A710_2136059))
 
+# Process ERRATA_A710_2147715 flag
+$(eval $(call assert_boolean,ERRATA_A710_2147715))
+$(eval $(call add_define,ERRATA_A710_2147715))
+
 # Process ERRATA_A710_2282622 flag
 $(eval $(call assert_boolean,ERRATA_A710_2282622))
 $(eval $(call add_define,ERRATA_A710_2282622))