Fix AUTO_RELASE (Reported by Niklas Larsson)

git-svn-id: https://svn.code.sf.net/p/chan-sccp-b/code/trunk@5420 43c1dc8c-776e-4df2-8ef1-6e829299be21
Remove two unnecessary device releases. Update sccp_channel_resume to use AUTO_RELEASE to put a previous channel on hold, before resuming.

git-svn-id: https://svn.code.sf.net/p/chan-sccp-b/code/trunk@5421 43c1dc8c-776e-4df2-8ef1-6e829299be21