feat(ras): add RAS system registers access test

FEAT_RAS introduces EL1 system registers to query error records, those
CPU specific parts of the RAS extension can be accessed independently of
any FFH/KFH handling setup or any system specific RAS implementation.

Add a test to verify that those registers can be read, when the CPUID
field advertises the MPAM (CPU) extension.

Change-Id: I7429fc815e7e0ee0cd736603966969b2cfb5f469
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
diff --git a/include/common/test_helpers.h b/include/common/test_helpers.h
index 8ca4cdf..1ab35ba 100644
--- a/include/common/test_helpers.h
+++ b/include/common/test_helpers.h
@@ -279,6 +279,14 @@
 		}                                                               \
 	} while (false)
 
+#define SKIP_TEST_IF_RAS_NOT_SUPPORTED()                                     \
+	do {                                                                 \
+		if(!is_feat_ras_present()){                                  \
+			tftf_testcase_printf("ARMv8.2-RAS not supported\n"); \
+			return TEST_RESULT_SKIPPED;                          \
+		}                                                            \
+	} while (false)
+
 #ifdef __aarch64__
 #define SKIP_TEST_IF_PA_SIZE_LESS_THAN(n)					\
 	do {									\