iwlegacy: Use dev_get_drvdata where possible

Instead of using to_pci_dev + pci_get_drvdata,
use dev_get_drvdata to make code simpler.
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/intel/iwlegacy/common.c

@@ -4942,8 +4942,7 @@ EXPORT_SYMBOL(il_add_beacon_time);
 static int
 il_pci_suspend(struct device *device)
 {
-	struct pci_dev *pdev = to_pci_dev(device);
-	struct il_priv *il = pci_get_drvdata(pdev);
+	struct il_priv *il = dev_get_drvdata(device);
 
 	/*
 	 * This function is called when system goes into suspend state