usb: gadget: pch_udc: enable MSI if hardware supports

Try to enable MSI in case hardware supports it. At least Intel Quark is
known SoC which indeed does.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/gadget/udc/pch_udc.c

@@ -3132,6 +3132,8 @@ static int pch_udc_probe(struct pci_dev *pdev,
 	if (pch_udc_pcd_init(dev))
 		return -ENODEV;
 
+	pci_enable_msi(pdev);
+
 	retval = devm_request_irq(&pdev->dev, pdev->irq, pch_udc_isr,
 				  IRQF_SHARED, KBUILD_MODNAME, dev);
 	if (retval) {