chan_iax2: nativebridge refactor, missed unlock bridgecallno
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Merged revisions 391143 from http://svn.asterisk.org/svn/asterisk/branches/1.8
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Merged revisions 391148 from http://svn.asterisk.org/svn/asterisk/branches/11


git-svn-id: http://svn.asterisk.org/svn/asterisk/trunk@391154 f38db490-d61c-443f-a65b-d21fe96a405b