test(realm): enhance realm memory exception tests for planes

Extend memory exception tests for planes.

Change-Id: Ifc98b8c67e85b04b36a78f16971d17f05d6a87d2
Signed-off-by: Shruti Gupta <shruti.gupta@arm.com>
diff --git a/realm/realm_payload_main.c b/realm/realm_payload_main.c
index ad98841..e654f1f 100644
--- a/realm/realm_payload_main.c
+++ b/realm/realm_payload_main.c
@@ -271,7 +271,7 @@
 	void (*func_ptr)(void);
 	rsi_ripas_type ripas;
 
-	base = realm_shared_data_get_my_host_val(HOST_ARG1_INDEX);
+	base = realm_shared_data_get_my_host_val(HOST_ARG3_INDEX);
 	rsi_ipa_state_get(base, base + PAGE_SIZE, &new_top, &ripas);
 	realm_printf("Initial ripas=%u\n", ripas);
 	/* Causes instruction abort */
@@ -286,7 +286,7 @@
 {
 	u_register_t base, new_top;
 	rsi_ripas_type ripas;
-	base = realm_shared_data_get_my_host_val(HOST_ARG1_INDEX);
+	base = realm_shared_data_get_my_host_val(HOST_ARG3_INDEX);
 	rsi_ipa_state_get(base, base + PAGE_SIZE, &new_top, &ripas);
 	realm_printf("Initial ripas=%u\n", ripas);
 	/* Causes data abort */
@@ -300,7 +300,7 @@
 {
 	u_register_t base, far, esr, elr;
 
-	base = realm_shared_data_get_my_host_val(HOST_ARG1_INDEX);
+	base = realm_shared_data_get_my_host_val(HOST_ARG3_INDEX);
 	far = read_far_el1();
 	esr = read_esr_el1();
 	elr = read_elr_el1();