drm/ast: Remove test for device from ast_pm_freeze()

The driver cannot suspend before it has loaded completely. So the test
for device pointers is not required. Remove it.

v3:
	* s/them/it/ in commit message
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200617080340.29584-3-tzimmermann@suse.de

drivers/gpu/drm/ast/ast_drv.c

@@ -188,9 +188,6 @@ static int ast_pm_freeze(struct device *dev)
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
 	struct drm_device *ddev = pci_get_drvdata(pdev);
-
-	if (!ddev || !ddev->dev_private)
-		return -ENODEV;
 	return ast_drm_freeze(ddev);
 }