USB: EHCI: ehci-mv: make the PHY optional

We may be using a NOP transceiver and those are treated specially by the
USB core and return -ENODEV with devm_phy_get().

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20191221065008.266445-3-lkundrak@v3.sk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/ehci-mv.c

@@ -116,7 +116,7 @@ static int mv_ehci_probe(struct platform_device *pdev)
 		ehci_mv->set_vbus = pdata->set_vbus;
 	}
 
-	ehci_mv->phy = devm_phy_get(&pdev->dev, "usb");
+	ehci_mv->phy = devm_phy_optional_get(&pdev->dev, "usb");
 	if (IS_ERR(ehci_mv->phy)) {
 		retval = PTR_ERR(ehci_mv->phy);
 		if (retval != -EPROBE_DEFER)