drm/gma500: use to_pci_dev()

Use to_pci_dev() instead of open-coding it.

Signed-off-by: Geliang Tang <[e-mail]>
Signed-off-by: Daniel Vetter <[e-mail]>

drivers/gpu/drm/gma500/power.c

···
  */
 int gma_power_suspend(struct device *_dev)
 {
-	struct pci_dev *pdev = container_of(_dev, struct pci_dev, dev);
+	struct pci_dev *pdev = to_pci_dev(_dev);
 	struct drm_device *dev = pci_get_drvdata(pdev);
 	struct drm_psb_private *dev_priv = dev->dev_private;
 
···
  */
 int gma_power_resume(struct device *_dev)
 {
-	struct pci_dev *pdev = container_of(_dev, struct pci_dev, dev);
+	struct pci_dev *pdev = to_pci_dev(_dev);
 	struct drm_device *dev = pci_get_drvdata(pdev);
 
 	mutex_lock(&power_mutex);