[IPV4] Use appropriate sysctl helpers for gc_min_interval_ms.

Because its type is int, inappropriate to use ulong helpers.
This also fixes inconsistency between sysctl and procfs.
Signed-off-by: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>

net/ipv4/route.c

@@ -2545,10 +2545,10 @@ ctl_table ipv4_route_table[] = {
 		.ctl_name	= NET_IPV4_ROUTE_GC_MIN_INTERVAL_MS,
 		.procname	= "gc_min_interval_ms",
 		.data		= &ip_rt_gc_min_interval,
-		.maxlen		= sizeof(unsigned long),
+		.maxlen		= sizeof(int),
 		.mode		= 0644,
-		.proc_handler	= &proc_doulongvec_ms_jiffies_minmax,
-		.strategy	= &sysctl_jiffies,
+		.proc_handler	= &proc_dointvec_ms_jiffies,
+		.strategy	= &sysctl_ms_jiffies,
 	},
 	{
 		.ctl_name	= NET_IPV4_ROUTE_GC_TIMEOUT,