Don't hold channel lock while sleeping/waiting for audio stream to get setup....

Don't hold channel lock while sleeping/waiting for audio stream to get setup. (issue #8834 reported by phsultan)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@51193 65c4cc65-6c06-0410-ace0-fbb531ad65f3