ipv6: coding style: comparison for inequality with NULL

The ipv6 code uses a mixture of coding styles. In some instances check for 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/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
index aa9ea6e..67e014d 100644
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c
@@ -223,7 +223,7 @@
 		}
 	}
 
-	if (cand != NULL)
+	if (cand)
 		return cand;
 
 	dev = ign->fb_tunnel_dev;
@@ -1105,7 +1105,7 @@
 		t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
 
 		if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
-			if (t != NULL) {
+			if (t) {
 				if (t->dev != dev) {
 					err = -EEXIST;
 					break;
@@ -1313,7 +1313,7 @@
 
 			t = rtnl_dereference(ign->tunnels[prio][h]);
 
-			while (t != NULL) {
+			while (t) {
 				/* If dev is in the same netns, it has already
 				 * been added to the list by the previous loop.
 				 */