net: ping: fix build failure

If CONFIG_PROC_SYSCTL=n the building process fails:

    ping.c:(.text+0x52af3): undefined reference to `inet_get_ping_group_range_net'

Moved inet_get_ping_group_range_net() to ping.c.

Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
index 41836ab..6a21da9 100644
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -187,6 +187,19 @@
 	return sk;
 }
 
+static void inet_get_ping_group_range_net(struct net *net, gid_t *low, gid_t *high)
+{
+	gid_t *data = net->ipv4.sysctl_ping_group_range;
+	unsigned seq;
+	do {
+		seq = read_seqbegin(&sysctl_local_ports.lock);
+
+		*low = data[0];
+		*high = data[1];
+	} while (read_seqretry(&sysctl_local_ports.lock, seq));
+}
+
+
 static int ping_init_sock(struct sock *sk)
 {
 	struct net *net = sock_net(sk);