This patch fixes the checkpatch issue of NULL comparison. Replace x == NULL
with !x, by using the following coccinelle script:

@disable is_null@
expression e;
@@
-e==NULL
+!e
Signed-off-by: NVarsha Rao <rvarsha016@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>