Fix a crash due to too few arguments to RetryDial.

(closes issue #14852)
Reported by: junky
Patches:
      retry_fix.diff uploaded by junky (license 177)



git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@187135 65c4cc65-6c06-0410-ace0-fbb531ad65f3

apps/app_dial.c

@@ -1872,7 +1872,7 @@ static int retrydial_exec(struct ast_channel *chan, void *data)
 		}
 	}
 	
-	if ((dialdata = strchr(dialdata, '|'))) {
+	if (dialdata && (dialdata = strchr(dialdata, '|'))) {
 		*dialdata++ = '\0';
 	} else {
 		ast_log(LOG_ERROR, "%s requires more arguments\n",rapp);