[patch] drm: mxsfb: drm_dev_alloc() returns error pointers

[Dan Carpenter]

We should be checking for IS_ERR() instead of NULL because
drm_dev_alloc() returns error pointers.

Fixes: 45d59d704080 ("drm: Add new driver for MXSFB controller")
Signed-off-by: Dan Carpenter <dan.carpenter at oracle.com>

diff --git a/drivers/gpu/drm/mxsfb/mxsfb_drv.c 
b/drivers/gpu/drm/mxsfb/mxsfb_drv.c
index 79a18bf48b54..955441f71500 100644
--- a/drivers/gpu/drm/mxsfb/mxsfb_drv.c
+++ b/drivers/gpu/drm/mxsfb/mxsfb_drv.c
@@ -395,8 +395,8 @@ static int mxsfb_probe(struct platform_device *pdev)
                pdev->id_entry = of_id->data;

        drm = drm_dev_alloc(&mxsfb_driver, &pdev->dev);
-       if (!drm)
-               return -ENOMEM;
+       if (IS_ERR(drm))
+               return PTR_ERR(drm);

        ret = mxsfb_load(drm, 0);
        if (ret)