Fixing sccp_pbx_call with DND (Mail: Crash 4.1 RC1 b4415))

git-svn-id: https://svn.code.sf.net/p/chan-sccp-b/code/trunk@4419 43c1dc8c-776e-4df2-8ef1-6e829299be21
Fix hangup during channel allocate (reported by bob).

git-svn-id: https://svn.code.sf.net/p/chan-sccp-b/code/trunk@4420 43c1dc8c-776e-4df2-8ef1-6e829299be21
Fix hangup during channel allocate (reported by bob).

git-svn-id: https://svn.code.sf.net/p/chan-sccp-b/code/trunk@4421 43c1dc8c-776e-4df2-8ef1-6e829299be21