use the actual given ip address for 'rtp set debug ip <foo>' instead of the word 'ip'

(closes issue #15711)
Reported by: davidw
Patches:
      2009082800-rtpdebug.diff.txt uploaded by mvanbaak (license 7)
Tested by: davidw


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@218107 65c4cc65-6c06-0410-ace0-fbb531ad65f3

res/res_rtp_asterisk.c

@@ -2400,7 +2400,7 @@ static char *rtp_do_debug_ip(struct ast_cli_args *a)
 	struct hostent *hp;
 	struct ast_hostent ahp;
 	int port = 0;
-	char *p, *arg = ast_strdupa(a->argv[3]);
+	char *p, *arg = ast_strdupa(a->argv[4]);
 
 	p = strstr(arg, ":");
 	if (p) {