net: ping: small changes

ping_table is not __read_mostly, since it contains one rwlock,
and is static to ping.c

ping_port_rover & ping_v4_lookup are static
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Vasiliy Kulikov <segoon@openwall.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/ping.c

@@ -49,9 +49,9 @@
 #include <net/checksum.h>
 
 
-struct ping_table ping_table __read_mostly;
+static struct ping_table ping_table;
 
-u16 ping_port_rover;
+static u16 ping_port_rover;
 
 static inline int ping_hashfn(struct net *net, unsigned num, unsigned mask)
 {
@@ -150,8 +150,8 @@ static void ping_v4_unhash(struct sock *sk)
 	}
 }
 
-struct sock *ping_v4_lookup(struct net *net, u32 saddr, u32 daddr,
-	 u16 ident, int dif)
+static struct sock *ping_v4_lookup(struct net *net, u32 saddr, u32 daddr,
+				   u16 ident, int dif)
 {
 	struct hlist_nulls_head *hslot = ping_hashslot(&ping_table, net, ident);
 	struct sock *sk = NULL;