Short circuit the loop in autoservice_run if there are no channels to poll.

If we continued, then the result would be calling poll() with a NULL
pollfd array. While this is fine with POSIX's poll(2) system call, those
who use Asterisk's internal poll mechanism (Darwin systems) would have
a failed assertion occur when poll is called.

(related to issue #10342)



git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@122713 65c4cc65-6c06-0410-ace0-fbb531ad65f3

main/autoservice.c

@@ -106,6 +106,10 @@ static void *autoservice_run(void *ign)
 
 		AST_LIST_UNLOCK(&aslist);
 
+		if (!x) {
+			continue;
+		}
+
 		chan = ast_waitfor_n(mons, x, &ms);
 		if (!chan) {
 			continue;