staging: comedi: ni_atmio: (!foo) preferred over (foo == NULL)

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/ni_atmio.c

@@ -250,7 +250,7 @@ static int ni_isapnp_find_board(struct pnp_dev **dev)
 					  ISAPNP_FUNCTION(ni_boards[i].
 							  isapnp_id), NULL);
 
-		if (isapnp_dev == NULL || isapnp_dev->card == NULL)
+		if (!isapnp_dev || !isapnp_dev->card)
 			continue;
 
 		if (pnp_device_attach(isapnp_dev) < 0)