usb: otg: support for multiple transceivers by a single controller

Add a linked list for keeping multiple PHY instances with different
types so that we can have separate USB2 and USB3 PHYs on one single
board. _get_phy_ has been changed so that the controller gets
the transceiver by type. _remove_phy_ has been added to let the phy
be removed from the phy list.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/otg/nop-usb-xceiv.c b/drivers/usb/otg/nop-usb-xceiv.c
index 33000da..803f958 100644
--- a/drivers/usb/otg/nop-usb-xceiv.c
+++ b/drivers/usb/otg/nop-usb-xceiv.c
@@ -117,7 +117,7 @@
 	nop->phy.otg->set_host		= nop_set_host;
 	nop->phy.otg->set_peripheral	= nop_set_peripheral;
 
-	err = usb_add_phy(&nop->phy);
+	err = usb_add_phy(&nop->phy, USB_PHY_TYPE_USB2);
 	if (err) {
 		dev_err(&pdev->dev, "can't register transceiver, err: %d\n",
 			err);
@@ -139,7 +139,7 @@
 {
 	struct nop_usb_xceiv *nop = platform_get_drvdata(pdev);
 
-	usb_add_phy(NULL);
+	usb_remove_phy(&nop->phy);
 
 	platform_set_drvdata(pdev, NULL);
 	kfree(nop->phy.otg);