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/igmp.c b/net/ipv4/igmp.c
index 27d204b..a3a697f 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -2370,7 +2370,7 @@
 		inet->mc_list = iml->next_rcu;
 		in_dev = inetdev_by_index(net, iml->multi.imr_ifindex);
 		(void) ip_mc_leave_src(sk, iml, in_dev);
-		if (in_dev != NULL)
+		if (in_dev)
 			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
 		/* decrease mem now to avoid the memleak warning */
 		atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
@@ -2590,10 +2590,10 @@
 		if (unlikely(!idev))
 			continue;
 		im = rcu_dereference(idev->mc_list);
-		if (likely(im != NULL)) {
+		if (likely(im)) {
 			spin_lock_bh(&im->lock);
 			psf = im->sources;
-			if (likely(psf != NULL)) {
+			if (likely(psf)) {
 				state->im = im;
 				state->idev = idev;
 				break;
@@ -2663,7 +2663,7 @@
 	__releases(rcu)
 {
 	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
-	if (likely(state->im != NULL)) {
+	if (likely(state->im)) {
 		spin_unlock_bh(&state->im->lock);
 		state->im = NULL;
 	}