xpp_sb3_pim: bad device configuration, camera-optional PIM?

[klauer]

Per Silke:

XPP:SB3 sort of exists, but we typically run this camera in the DAQ. I believe we will be upgrading it to one of the new USB3 Allied cameras in the future for which no IOC eixsts now. (-> XPP:SB3 (xpp's yag2) is more complicated: we want this device as we regularly use it, but we don't use the camera piece. I don't know if we should make a camera-optional PIM object?)

[ZLLentz]

It's pretty trivial to make a "no camera" PIM device. Camera-optional will make everything hard, and will be especially problematic if the only way to "know" if it should be there or not is connected/disconnected PVs.