drm/gma500: Fix wrong pointer passed to PTR_ERR()

PTR_ERR() should access the value just tested by IS_ERR(),
otherwise the wrong error code will be returned.

Signed-off-by: Yang Yingliang <[e-mail]>
Signed-off-by: Thomas Zimmermann <[e-mail]>
Reviewed-by: Thomas Zimmermann <[e-mail]>
Fixes: c2f17e60cbe1 ("drm/gma500: Embed struct drm_device in struct drm_psb_private")
Reported-by: Hulk Robot <[e-mail]>
Cc: Thomas Zimmermann <[e-mail]>
Cc: Patrik Jakobsson <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/gma500/psb_drv.c

···
 
 	dev_priv = devm_drm_dev_alloc(&pdev->dev, &driver, struct drm_psb_private, dev);
 	if (IS_ERR(dev_priv))
-		return PTR_ERR(dev);
+		return PTR_ERR(dev_priv);
 	dev = &dev_priv->dev;
 
 	pci_set_drvdata(pdev, dev);