Remove redundant check

We only setup the timer if we are configured to control iTunes, so there should be no reason to check that we control iTunes, before we check if we have setup the timer (only to tear it down).

This change is motivated by using the timer to control (other) third party music players.
Pause Spotify when video playback starts

This mimics the current iTunes behavior. For resuming, we piggyback on the iTunes resume timer, it might make sense to rename this timer and associated trigger method to indicate that it is for multiple third party music players.