gimbal: correctly set gimbal_device_id

When we use a gimbal connected via "RC", so PWM via the Aux channels, we
need to set the gimbal_device_id to 1 as per the protocol.

This was missing for GIMBAL_DEVICE_ATTITUDE_STATUS, so I added that, and
fixed the name of that variable while at it.

msg/GimbalDeviceAttitudeStatus.msg

@@ -16,5 +16,8 @@ float32 angular_velocity_y
 float32 angular_velocity_z
 
 uint32 failure_flags
+float32 delta_yaw
+float32 delta_yaw_velocity
+uint8 gimbal_device_id
 
 bool received_from_mavlink

msg/GimbalDeviceInformation.msg

@@ -33,4 +33,4 @@ float32 pitch_max # [rad]
 float32 yaw_min # [rad]
 float32 yaw_max # [rad]
 
-uint8 gimbal_device_compid
+uint8 gimbal_device_id