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/gadget/pxa27x_udc.c b/drivers/usb/gadget/pxa27x_udc.c
index b982304..8f744aa 100644
--- a/drivers/usb/gadget/pxa27x_udc.c
+++ b/drivers/usb/gadget/pxa27x_udc.c
@@ -2464,7 +2464,7 @@
 
 	udc->dev = &pdev->dev;
 	udc->mach = pdev->dev.platform_data;
-	udc->transceiver = usb_get_phy();
+	udc->transceiver = usb_get_phy(USB_PHY_TYPE_USB2);
 
 	gpio = udc->mach->gpio_pullup;
 	if (gpio_is_valid(gpio)) {