Make sure the channel is being hangup when softswitch has failed

git-svn-id: https://svn.code.sf.net/p/chan-sccp-b/code/trunk@5548 43c1dc8c-776e-4df2-8ef1-6e829299be21
Use AUTO_RELEASE for sccp_wrapper_asterisk???_hangup

git-svn-id: https://svn.code.sf.net/p/chan-sccp-b/code/trunk@5549 43c1dc8c-776e-4df2-8ef1-6e829299be21
Fix compile warnings

git-svn-id: https://svn.code.sf.net/p/chan-sccp-b/code/trunk@5550 43c1dc8c-776e-4df2-8ef1-6e829299be21