Unlock before returning, when extension doesn't exist.

(closes issue #13807)
 Reported by: eliel
 Patches: 
       chan_local.c.patch uploaded by eliel (license 64)


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@152922 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_local.c

@@ -489,6 +489,7 @@ static int local_call(struct ast_channel *ast, char *dest, int timeout)
 
 	if (!ast_exists_extension(NULL, p->chan->context, p->chan->exten, 1, p->owner->cid.cid_num)) {
 		ast_log(LOG_NOTICE, "No such extension/context %s@%s while calling Local channel\n", p->chan->exten, p->chan->context);
+		ast_mutex_unlock(&p->lock);
 		return -1;
 	}