Currently, if we start decoding while the pause flag is set, we open the
audio device and leave it opened, blocking other apps from using it.  The
obvious thing to do is to not open the audio device if the pause flag is
set, but the open call also sets the audio format.  Therefore I'm leaving
the open call in, and just closing it immediately afterwards if the pause
flag is set.

git-svn-id: https://svn.musicpd.org/mpd/trunk@6745 09075e82-0dd4-0310-85a5-a0d7c8717e4f