feat(trf): enable trace filter control register access from lower NS EL

Introduced a build flag 'ENABLE_TRF_FOR_NS' to enable trace filter
control registers access in NS-EL2, or NS-EL1 (when NS-EL2 is
implemented but unused).

Change-Id: If3f53b8173a5573424b9a405a4bd8c206ffdeb8c
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
diff --git a/lib/el3_runtime/aarch64/context_mgmt.c b/lib/el3_runtime/aarch64/context_mgmt.c
index 0eb800a..52102dd 100644
--- a/lib/el3_runtime/aarch64/context_mgmt.c
+++ b/lib/el3_runtime/aarch64/context_mgmt.c
@@ -24,6 +24,7 @@
 #include <lib/extensions/sve.h>
 #include <lib/extensions/sys_reg_trace.h>
 #include <lib/extensions/trbe.h>
+#include <lib/extensions/trf.h>
 #include <lib/extensions/twed.h>
 #include <lib/utils.h>
 
@@ -359,6 +360,10 @@
 	sys_reg_trace_enable(ctx);
 #endif /* ENABLE_SYS_REG_TRACE_FOR_NS */
 
+#if ENABLE_TRF_FOR_NS
+	trf_enable();
+#endif /* ENABLE_TRF_FOR_NS */
+
 #endif
 }