AMU: Implement support for aarch32

The `ENABLE_AMU` build option can be used to enable the
architecturally defined AMU counters.  At present, there is no support
for the auxiliary counter group.

Change-Id: Ifc7532ef836f83e629f2a146739ab61e75c4abc8
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>
diff --git a/lib/el3_runtime/aarch32/context_mgmt.c b/lib/el3_runtime/aarch32/context_mgmt.c
index a8672d6..76e440e3 100644
--- a/lib/el3_runtime/aarch32/context_mgmt.c
+++ b/lib/el3_runtime/aarch32/context_mgmt.c
@@ -4,6 +4,7 @@
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
+#include <amu.h>
 #include <arch.h>
 #include <arch_helpers.h>
 #include <assert.h>
@@ -132,6 +133,9 @@
 static void enable_extensions_nonsecure(int el2_unused)
 {
 #if IMAGE_BL32
+#if ENABLE_AMU
+	amu_enable(el2_unused);
+#endif
 #endif
 }