feat(pauth): add/modify helpers to support QARMA3

QARMA3 is a pointer authentication algorithm that generates
the PAC codes.

The is_armv8_3_pauth_present() helper was modified in order to
consider the presence of the QARMA3 algorithm (i.e.: when
ID_AA64ISAR2_EL1.{GPA3, APA3} fields are not 0.

In addition, helper is_feat_pacqarma3_present() was implemented to
explicitly detect the presence of QARMA3 algorithm.

Signed-off-by: Juan Pablo Conde <juanpablo.conde@arm.com>
Change-Id: I68e8fa7f8b7ca50d74ae0a2f5f182236d68f3d7b
diff --git a/include/arch/aarch64/arch.h b/include/arch/aarch64/arch.h
index e55d33f..37caf09 100644
--- a/include/arch/aarch64/arch.h
+++ b/include/arch/aarch64/arch.h
@@ -261,6 +261,15 @@
 #define ID_AA64ISAR1_SB_SUPPORTED	ULL(0x1)
 #define ID_AA64ISAR1_SB_NOT_SUPPORTED	ULL(0x0)
 
+/* ID_AA64ISAR2_EL1 definitions */
+#define ID_AA64ISAR2_EL1		S3_0_C0_C6_2
+
+#define ID_AA64ISAR2_GPA3_SHIFT		U(8)
+#define ID_AA64ISAR2_GPA3_MASK		ULL(0xf)
+
+#define ID_AA64ISAR2_APA3_SHIFT		U(12)
+#define ID_AA64ISAR2_APA3_MASK		ULL(0xf)
+
 /* ID_AA64MMFR0_EL1 definitions */
 #define ID_AA64MMFR0_EL1_PARANGE_SHIFT	U(0)
 #define ID_AA64MMFR0_EL1_PARANGE_MASK	ULL(0xf)