aty128fb: use pdev->pm_cap instead of pci_find_capability(..,PCI_CAP_ID_PM)

Pci core has been saved pm cap register offset by pdev->pm_cap in pci_pm_init()
in init path. So we can use pdev->pm_cap instead of using
pci_find_capability(pdev, PCI_CAP_ID_PM) for better performance and simplified code.
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: linux-fbdev@vger.kernel.org
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drivers/video/aty/aty128fb.c

@@ -2016,7 +2016,7 @@ static int aty128_init(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	aty128_init_engine(par);
 
-	par->pm_reg = pci_find_capability(pdev, PCI_CAP_ID_PM);
+	par->pm_reg = pdev->pm_cap;
 	par->pdev = pdev;
 	par->asleep = 0;
 	par->lock_blank = 0;