serial: 8250_lpss: get IRQ via pci_irq_vector()

Instead of a direct assignment use pci_irq_vector() call as it's done for the
other case.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/8250/8250_lpss.c

@@ -174,7 +174,7 @@ static void qrk_serial_setup_dma(struct lpss8250 *lpss, struct uart_port *port)
 	int ret;
 
 	chip->dev = &pdev->dev;
-	chip->irq = pdev->irq;
+	chip->irq = pci_irq_vector(pdev, 0);
 	chip->regs = pci_ioremap_bar(pdev, 1);
 	chip->pdata = &qrk_serial_dma_pdata;