This patch introduces the use of the macro IS_ERR_OR_NULL in place of
tests for NULL and IS_ERR.

The following Coccinelle semantic patch was used for making the change:

@@
expression e;
@@

- e == NULL || IS_ERR(e)
+ IS_ERR_OR_NULL(e)
 || ...
Signed-off-by: NHimangi Saraogi <himangi774@gmail.com>
Acked-by: NJulia Lawall <julia.lawall@lip6.fr>
Acked-by: NPravin B Shelar <pshelar@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>