fix(cpus): workaround for Cortex-A520 erratum 2630792

Cortex-A520 erratum is a Cat B erratum that applies
to revisions r0p0 and r0p1 and is still open.
The workaround is to set CPUACTLR_EL1[38] to 1.

SDEN Documentation:
https://developer.arm.com/documentation/SDEN-2444153/latest

Change-Id: Idb6f32f680ee1378a57c2d2f809ea847fffe5910
Signed-off-by: Sona Mathew <sonarebecca.mathew@arm.com>
diff --git a/include/lib/cpus/aarch64/cortex_a520.h b/include/lib/cpus/aarch64/cortex_a520.h
index 4176981..1c5f886 100644
--- a/include/lib/cpus/aarch64/cortex_a520.h
+++ b/include/lib/cpus/aarch64/cortex_a520.h
@@ -15,6 +15,11 @@
 #define CORTEX_A520_CPUECTLR_EL1				S3_0_C15_C1_4
 
 /*******************************************************************************
+ * CPU Auxiliary Control register 1 specific definitions.
+ ******************************************************************************/
+#define CORTEX_A520_CPUACTLR_EL1				S3_0_C15_C1_0
+
+/*******************************************************************************
  * CPU Power Control register specific definitions
  ******************************************************************************/
 #define CORTEX_A520_CPUPWRCTLR_EL1				S3_0_C15_C2_7