usb: new board-specific USB init interface

This commit unifies board-specific USB initialization implementations
under one symbol (usb_board_init), declaration of which is available in
usb.h.

New API allows selective initialization of USB controllers whenever needed.

Signed-off-by: Mateusz Zalega <m.zalega@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
Cc: Marek Vasut <marex@denx.de>
Cc: Lukasz Majewski <l.majewski@samsung.com>
diff --git a/board/ti/panda/panda.c b/board/ti/panda/panda.c
index bc3c292..3724e81 100644
--- a/board/ti/panda/panda.c
+++ b/board/ti/panda/panda.c
@@ -279,7 +279,7 @@
 	utmi_clk |= HSUSBHOST_CLKCTRL_CLKSEL_UTMI_P1_MASK;
 	sr32((void *)CM_L3INIT_HSUSBHOST_CLKCTRL, 0, 32, utmi_clk);
 
-	ret = omap_ehci_hcd_init(&usbhs_bdata, hccr, hcor);
+	ret = omap_ehci_hcd_init(index, &usbhs_bdata, hccr, hcor);
 	if (ret < 0)
 		return ret;