test(realm): fix pauth exception test

Pauth exception tests fail when FEAT_PAUTH2 is enabled.
Fix error, return success if exception handler is hit,
remove PAC fields check since the PAC fields can vary based
on the configuration of the system.

Signed-off-by: Shruti Gupta <shruti.gupta@arm.com>
Change-Id: Id6312c7ebb7202302d8465f772deb176e419bded
diff --git a/realm/realm_pauth.c b/realm/realm_pauth.c
index 31b26e7..9c507b6 100644
--- a/realm/realm_pauth.c
+++ b/realm/realm_pauth.c
@@ -19,18 +19,10 @@
 
 static bool exception_handler(void)
 {
-	u_register_t lr = read_elr_el1();
-
 	/* Disable PAuth to avoid further PAuth faults. */
 	pauth_disable();
 
-	/* Check for PAuth exception. */
-	/* Note- PAuth decode instruction clobbers PAC Fields[63:56] in case of error. */
-	if (lr & (0xFFULL << 56U)) {
-		rsi_exit_to_host(HOST_CALL_EXIT_SUCCESS_CMD);
-	}
-
-	rsi_exit_to_host(HOST_CALL_EXIT_FAILED_CMD);
+	rsi_exit_to_host(HOST_CALL_EXIT_SUCCESS_CMD);
 
 	/* Does not return. */
 	return false;