Fix file descriptor leak in 3-way call
Usage of ast_channel_get_bridge_channel requires use of ao2_ref() or ao2_cleanup().
Too many references changed lifetime of an object and caused file descriptor leakage every 3way call.
Usage of ast_channel_get_bridge_channel requires use of ao2_ref() or ao2_cleanup().
Too many references changed lifetime of an object and caused file descriptor leakage every 3way call.