This change prevents a crash from occurring if res_musiconhold.so

is unloaded and then Asterisk is stopped. The problem was that
we are not unregistering the ast_moh_destroy function at exit.

(closes issue #13761)
Reported by: eliel
Patches:
      res_musiconhold.c.patch uploaded by eliel (license 64)



git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@157592 65c4cc65-6c06-0410-ace0-fbb531ad65f3

res/res_musiconhold.c

@@ -1672,6 +1672,7 @@ static int unload_module(void)
 	res |= ast_unregister_application(start_moh);
 	res |= ast_unregister_application(stop_moh);
 	ast_cli_unregister_multiple(cli_moh, sizeof(cli_moh) / sizeof(struct ast_cli_entry));
+	ast_unregister_atexit(ast_moh_destroy);
 	return res;
 }