ipv4: coding style: comparison for inequality with NULL

The ipv4 code uses a mixture of coding styles. In some instances check
for non-NULL pointer is done as x != NULL and sometimes as x. x is
preferred according to checkpatch and this patch makes the code
consistent by adopting the latter form.

No changes detected by objdiff.

Signed-off-by: Ian Morris <ipm@chirality.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/inet_timewait_sock.c b/net/ipv4/inet_timewait_sock.c
index f38e387..118f0f1 100644
--- a/net/ipv4/inet_timewait_sock.c
+++ b/net/ipv4/inet_timewait_sock.c
@@ -173,7 +173,7 @@
 	struct inet_timewait_sock *tw =
 		kmem_cache_alloc(sk->sk_prot_creator->twsk_prot->twsk_slab,
 				 GFP_ATOMIC);
-	if (tw != NULL) {
+	if (tw) {
 		const struct inet_sock *inet = inet_sk(sk);
 
 		kmemcheck_annotate_bitfield(tw, flags);