Make a BeamstopAndBacklight device for i24 to avoid collisions.

[noemifrisina]

On I24 the beamstop has been commissioned with an additional rotation axis around y (PV: BL24I-MO-BS-01:ROTY).
This motor is not controlled by the positioner, which move the x,y,z motors.
Because of the relative positions of the backlight and the beamstop, it is important to make sure that the backlight is in the "OUT" position before attempting to move the ROTY motor.

To avoid any collisions, there should be a composite device that upon a request to move ROTY checks the backlight and does not allow the move unless it's in the OUT position. The beamstop motor may still be moved out of the way if needed by using the positioner to move the other motors.

Acceptance Criteria

• There is a device connecting to I24 that controls the beamstop and backlight moves