test(realm): add support for planes shared buffer

- Add support for per plane shared buffer.
- Map shared buffer in all Aux RTT if
  realm uses multiple RTTs.
- Support realm_printf for all planes.

Signed-off-by: Shruti Gupta <shruti.gupta@arm.com>
Change-Id: Ie6924bcb9e9bb3b8c368f796d33f84f4f6821935
diff --git a/realm/realm_payload_main.c b/realm/realm_payload_main.c
index eb4c9aa..2556c11 100644
--- a/realm/realm_payload_main.c
+++ b/realm/realm_payload_main.c
@@ -270,7 +270,7 @@
 	/* No serror handler registered by default */
 	unregister_custom_serror_handler();
 
-	realm_set_shared_structure((host_shared_data_t *)realm_get_ns_buffer());
+	realm_set_shared_structure(realm_get_ns_buffer());
 
 	if (realm_get_my_shared_structure() != NULL) {
 		uint8_t cmd = realm_shared_data_get_my_realm_cmd();