feat(trbe): enable access to trace buffer control registers from lower NS EL

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

Change-Id: I285a672ccd395eebd377714c992bb21062a729cc
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
diff --git a/include/arch/aarch64/arch.h b/include/arch/aarch64/arch.h
index d71ec00..47e02ce 100644
--- a/include/arch/aarch64/arch.h
+++ b/include/arch/aarch64/arch.h
@@ -192,6 +192,11 @@
 #define ID_AA64DFR0_PMS_SHIFT	U(32)
 #define ID_AA64DFR0_PMS_MASK	ULL(0xf)
 
+/* ID_AA64DFR0_EL1.TraceBuffer definitions */
+#define ID_AA64DFR0_TRACEBUFFER_SHIFT		U(44)
+#define ID_AA64DFR0_TRACEBUFFER_MASK		ULL(0xf)
+#define ID_AA64DFR0_TRACEBUFFER_SUPPORTED	ULL(1)
+
 /* ID_AA64DFR0_EL1.MTPMU definitions (for ARMv8.6+) */
 #define ID_AA64DFR0_MTPMU_SHIFT		U(48)
 #define ID_AA64DFR0_MTPMU_MASK		ULL(0xf)