Fix spurious mission warning

src/modules/navigator/mission.cpp

@@ -656,8 +656,10 @@ Mission::read_mission_item(bool onboard, bool is_current, struct mission_item_s
 	for (int i = 0; i < 10; i++) {
 
 		if (*mission_index_ptr < 0 || *mission_index_ptr >= (int)mission->count) {
-			/* mission item index out of bounds */
-			mavlink_and_console_log_critical(_navigator->get_mavlink_fd(), "[wpm] err: index: %d, max: %d", *mission_index_ptr, (int)mission->count);
+			/* mission item index out of bounds - if they are equal, we just reached the end */
+			if (*mission_index_ptr != (int)mission->count) {
+				mavlink_and_console_log_critical(_navigator->get_mavlink_fd(), "[wpm] err: index: %d, max: %d", *mission_index_ptr, (int)mission->count);
+			}
 			return false;
 		}