Add workaround for errata 1220197 for Cortex-A76

Streaming store under specific conditions might cause deadlock or data
corruption. Set bit 25:24 of CPUECTLR_EL1, which disables write
streaming to the L2 to prevent this.

Change-Id: Ib5cabb997b35ada78b27e75787afd610ea606dcf
Signed-off-by: Louis Mayencourt <louis.mayencourt@arm.com>
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index 4fe8ea1..3dcaecf 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -135,6 +135,10 @@
 # only to revision <= r2p0 of the Cortex A76 cpu.
 ERRATA_A76_1130799	?=0
 
+# Flag to apply erratum 1220197 workaround during reset. This erratum applies
+# only to revision <= r2p0 of the Cortex A76 cpu.
+ERRATA_A76_1220197	?=0
+
 # Flag to apply T32 CLREX workaround during reset. This erratum applies
 # only to r0p0 and r1p0 of the Neoverse N1 cpu.
 ERRATA_N1_1043202	?=1
@@ -220,6 +224,10 @@
 $(eval $(call assert_boolean,ERRATA_A76_1130799))
 $(eval $(call add_define,ERRATA_A76_1130799))
 
+# Process ERRATA_A76_1220197 flag
+$(eval $(call assert_boolean,ERRATA_A76_1220197))
+$(eval $(call add_define,ERRATA_A76_1220197))
+
 # Process ERRATA_N1_1043202 flag
 $(eval $(call assert_boolean,ERRATA_N1_1043202))
 $(eval $(call add_define,ERRATA_N1_1043202))