remove Wpacked and cleanup unused warning flags

src/modules/sensors/CMakeLists.txt

@@ -35,9 +35,8 @@ px4_add_module(
 	MODULE modules__sensors
 	MAIN sensors
 	PRIORITY "SCHED_PRIORITY_MAX-5"
-	STACK_MAIN 1200
+	STACK_MAIN 1300
 	COMPILE_FLAGS
-		-Wno-type-limits
 		-O3
 	SRCS
 		sensors.cpp

src/modules/sensors/sensors.cpp

@@ -1945,7 +1945,7 @@ Sensors::rc_poll()
 			if (_parameters.rc_map_flightmode > 0) {
 
 				/* the number of valid slots equals the index of the max marker minus one */
-				const unsigned num_slots = manual_control_setpoint_s::MODE_SLOT_MAX;
+				const int num_slots = manual_control_setpoint_s::MODE_SLOT_MAX;
 
 				/* the half width of the range of a slot is the total range
 				 * divided by the number of slots, again divided by two