[PATCH -next] drm/shmob: Fix return value check in shmob_drm_probe

[Simon Horman]

On Mon, Dec 17, 2018 at 05:18:30PM +0800, YueHaibing wrote:
> In case of error, the function devm_ioremap_resource() returns ERR_PTR()
> and never returns NULL. The NULL test in the return value check should
> be replaced with IS_ERR().
> 
> Fixes: 8f1597c8f1a5 ("drm: shmobile: Perform initialization/cleanup at probe/remove time")
> Signed-off-by: YueHaibing <yuehaibing at huawei.com>

Reviewed-by: Simon Horman <horms+renesas at verge.net.au>