feat(brbe): test that EL3 has properly enabled access to BRBE

Access to FEAT_BRBE control registers must be explicitly enabled in EL3,
this simple test just ensures that the registers are accessible or traps
to EL3, similar to the TRBE test.

Signed-off-by: John Powell <john.powell@arm.com>
Change-Id: I0a25c5ce6beb6aa96b9428264b75cb3569ac535a
diff --git a/tftf/tests/tests-cpu-extensions.mk b/tftf/tests/tests-cpu-extensions.mk
index 4600e7f..0719486 100644
--- a/tftf/tests/tests-cpu-extensions.mk
+++ b/tftf/tests/tests-cpu-extensions.mk
@@ -7,6 +7,7 @@
 TESTS_SOURCES	+=	$(addprefix tftf/tests/,			\
 	extensions/afp/test_afp.c					\
 	extensions/amu/test_amu.c					\
+	extensions/brbe/test_brbe.c					\
 	extensions/ecv/test_ecv.c					\
 	extensions/fgt/test_fgt.c					\
 	extensions/mte/test_mte.c					\