Add tests for MTE support

TF-A now has support for the new Memory Tagging Extension in ARMv8.5,
see commit 91624b7fed52 ("Merge changes from topic "jc/mte_enable"
into integration").

This patch creates and enables tests to ensure that the extension is
being properly enabled and that no undesired leakages occur.

Change-Id: I7708fb23a12e2f35a97533f296aaa53db776ddd2
Signed-off-by: Justin Chadwell <justin.chadwell@arm.com>
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
diff --git a/include/lib/aarch64/arch_helpers.h b/include/lib/aarch64/arch_helpers.h
index 9d1ebb8..d16960a 100644
--- a/include/lib/aarch64/arch_helpers.h
+++ b/include/lib/aarch64/arch_helpers.h
@@ -469,6 +469,12 @@
 DEFINE_RENAME_SYSREG_RW_FUNCS(apgakeyhi_el1, APGAKeyHi_EL1)
 DEFINE_RENAME_SYSREG_RW_FUNCS(apgakeylo_el1, APGAKeyLo_EL1)
 
+/* MTE registers */
+DEFINE_RENAME_SYSREG_RW_FUNCS(tfsre0_el1, TFSRE0_EL1)
+DEFINE_RENAME_SYSREG_RW_FUNCS(tfsr_el1, TFSR_EL1)
+DEFINE_RENAME_SYSREG_RW_FUNCS(rgsr_el1, RGSR_EL1)
+DEFINE_RENAME_SYSREG_RW_FUNCS(gcr_el1, GCR_EL1)
+
 #define IS_IN_EL(x) \
 	(GET_EL(read_CurrentEl()) == MODE_EL##x)