Replace arm_request and mode_request with combined action_request

Which saves flash space, log size and is extensible to handle e.g.
the VTOL transition and future actions.

msg/CMakeLists.txt

@@ -37,6 +37,7 @@ cmake_policy(SET CMP0057 NEW)
 include(px4_list_make_absolute)
 
 set(msg_files
+	action_request.msg
 	actuator_armed.msg
 	actuator_controls.msg
 	actuator_controls_status.msg
@@ -47,7 +48,6 @@ set(msg_files
 	airspeed.msg
 	airspeed_validated.msg
 	airspeed_wind.msg
-	arm_request.msg
 	autotune_attitude_control_status.msg
 	battery_status.msg
 	camera_capture.msg
@@ -109,7 +109,6 @@ set(msg_files
 	mavlink_log.msg
 	mission.msg
 	mission_result.msg
-	mode_request.msg
 	mount_orientation.msg
 	multirotor_motor_limits.msg
 	navigator_mission_item.msg

msg/action_request.msg

@@ -6,8 +6,12 @@ uint8 ACTION_ARM = 1
 uint8 ACTION_TOGGLE_ARMING = 2
 uint8 ACTION_UNKILL = 3
 uint8 ACTION_KILL = 4
+uint8 ACTION_SWITCH_MODE = 5
 
 uint8 source # how the request was triggered
 uint8 SOURCE_RC_STICK_GESTURE = 0
 uint8 SOURCE_RC_SWITCH = 1
 uint8 SOURCE_RC_BUTTON = 2
+uint8 SOURCE_RC_MODE_SLOT = 3
+
+uint8 mode # for ACTION_SWITCH_MODE what mode is requested according to commander_state.MAIN_STATE_

msg/mode_request.msg

@@ -1,7 +0,0 @@
-uint64 timestamp # time since system start (microseconds)
-
-uint8 mode # what mode is requested according to commander_state.MAIN_STATE_
-
-uint8 source # how the request was triggered
-uint8 SOURCE_RC_MODE_SLOT = 0
-uint8 SOURCE_RC_SWITCH = 1