msg/vehicle_odometry.msg: simplify covariance handling and update all usage (#19966)

- replace float32[21] URT covariances with smaller dedicated position/velocity/orientation variances (the crossterms are unused, awkward, and relatively costly)
 - these are easier to casually inspect and more representative of what's actually being used currently and reduces the size of vehicle_odometry_s quite a bit
 - ekf2: add new helper to get roll/pitch/yaw covariances
 - mavlink: receiver ODOMETRY handle more frame types for both pose (MAV_FRAME_LOCAL_NED, MAV_FRAME_LOCAL_ENU, MAV_FRAME_LOCAL_FRD, MAV_FRAME_LOCAL_FLU) and velocity (MAV_FRAME_LOCAL_NED, MAV_FRAME_LOCAL_ENU, MAV_FRAME_LOCAL_FRD, MAV_FRAME_LOCAL_FLU, MAV_FRAME_BODY_FRD)
 - mavlink: delete unused ATT_POS_MOCAP stream (this is just a passthrough)

Co-authored-by: Mathieu Bresciani <brescianimathieu@gmail.com>

src/modules/mavlink/mavlink_messages.cpp

@@ -120,7 +120,6 @@
 
 #if !defined(CONSTRAINED_FLASH)
 # include "streams/ADSB_VEHICLE.hpp"
-# include "streams/ATT_POS_MOCAP.hpp"
 # include "streams/AUTOPILOT_STATE_FOR_GIMBAL_DEVICE.hpp"
 # include "streams/DEBUG.hpp"
 # include "streams/DEBUG_FLOAT_ARRAY.hpp"
@@ -401,9 +400,6 @@ static const StreamListItem streams_list[] = {
 #if defined(VIBRATION_HPP)
 	create_stream_list_item<MavlinkStreamVibration>(),
 #endif // VIBRATION_HPP
-#if defined(ATT_POS_MOCAP_HPP)
-	create_stream_list_item<MavlinkStreamAttPosMocap>(),
-#endif // ATT_POS_MOCAP_HPP
 #if defined(AUTOPILOT_STATE_FOR_GIMBAL_DEVICE_HPP)
 	create_stream_list_item<MavlinkStreamAutopilotStateForGimbalDevice>(),
 #endif // AUTOPILOT_STATE_FOR_GIMBAL_DEVICE_HPP