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/musb/ux500.c b/drivers/usb/musb/ux500.c
index 53006b1..46cf80a 100644
--- a/drivers/usb/musb/ux500.c
+++ b/drivers/usb/musb/ux500.c
@@ -37,7 +37,7 @@
 
 static int ux500_musb_init(struct musb *musb)
 {
-	musb->xceiv = usb_get_phy();
+	musb->xceiv = usb_get_phy(USB_PHY_TYPE_USB2);
 	if (!musb->xceiv) {
 		pr_err("HS USB OTG: no transceiver configured\n");
 		return -ENODEV;