Output records don't need to be polled

[bhill-slac]

No need to poll output records.
About the only reason I can see for polling output records would be to pick up any
changes made via web UI, however, this can introduce race conditions where
an earlier web UI change to a value could be picked up by the output record which
then overwrites a subsequent web UI change if they are close enough together.

[ffeldbauer]

At least for the bo record the reason is simple: E.g. a hardware interrupt which produces an emergency off will set the Control bit 3 (channel on/off) to 0.
I want to have the corresponding bo record in EPICS to update, otherwise I cannot directly switch the channel on again with a GUI but first have to switch if off, although it is already off....
When I was writing the code there were other scenarios, where set values can change by other means too, which is why they are polled.