refactor(cpufeat): separate the EL2 and EL3 enablement code

Combining the EL2 and EL3 enablement code necessitates that it must be
called at el3_exit, which is the only place with enough context to make
the decision of what needs to be set.
Decouple them to allow them to be called from elsewhere.

Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
Change-Id: I147764c42771e7d4100699ec8fae98dac0a505c0
diff --git a/lib/el3_runtime/aarch32/context_mgmt.c b/lib/el3_runtime/aarch32/context_mgmt.c
index 6414aaa..b60b8e0 100644
--- a/lib/el3_runtime/aarch32/context_mgmt.c
+++ b/lib/el3_runtime/aarch32/context_mgmt.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016-2023, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2023, Arm Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -142,19 +142,19 @@
 	}
 
 	if (is_feat_sys_reg_trace_supported()) {
-		sys_reg_trace_enable();
+		sys_reg_trace_init_el3();
 	}
 
 	if (is_feat_trf_supported()) {
-		trf_enable();
+		trf_init_el3();
 	}
 
 	/*
 	 * Also applies to PMU < v3. The PMU is only disabled for EL3 and Secure
 	 * state execution. This does not affect lower NS ELs.
 	 */
-	pmuv3_disable_el3();
-#endif
+	pmuv3_init_el3();
+#endif /*  IMAGE_BL32 */
 }
 
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