serial: 8250_exar: Use dev_get_drvdata() directly in PM callbacks

PM callbacks take struct device pointer as a parameter, use
dev_get_drvdata() to retrieve it instead of unneeded double
loop of referencing via pci_get_drvdata(to_pci_dev(dev)).
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240219150627.2101198-3-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/8250/8250_exar.c

@@ -760,8 +760,7 @@ static void exar_pci_remove(struct pci_dev *pcidev)
 
 static int __maybe_unused exar_suspend(struct device *dev)
 {
-	struct pci_dev *pcidev = to_pci_dev(dev);
-	struct exar8250 *priv = pci_get_drvdata(pcidev);
+	struct exar8250 *priv = dev_get_drvdata(dev);
 	unsigned int i;
 
 	for (i = 0; i < priv->nr; i++)