[IPVS]: Reverse valid ip_vs_ftp ports fix: port check approach

This patch reverses 3f5af5b353ca36aca4f8a46e3da2172f669dbbbc as
a better fix was suggested by Patrick McHardy.

Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/ipvs/ip_vs_ftp.c

@@ -365,12 +365,6 @@ static int __init ip_vs_ftp_init(void)
 	for (i=0; i<IP_VS_APP_MAX_PORTS; i++) {
 		if (!ports[i])
 			continue;
-		if (ports[i] < 0 || ports[i] > 0xffff) {
-			IP_VS_WARNING("ip_vs_ftp: Ignoring invalid "
-				      "configuration port[%d] = %d\n",
-				      i, ports[i]);
-			continue;
-		}
 		ret = register_ip_vs_app_inc(app, app->protocol, ports[i]);
 		if (ret)
 			break;