imx: ventana: fix UMS support

imx: ventana: fix UMS support

The Gateworks Ventana boards have always had usb0=usbh1 and usb1=usbotg
because OTG is often subloaded on these boards and a bit in the EEPROM
which flagging that OTG is subloaded is used to remove the dt node via the
alias.

U-Boot DM_USB UMS requires the usb0 alias be assigned to the usbotg
so fix the usb0 alias in order for UMS to work.

Fixes dff2be3b7ced: ("imx: ventana: enable dm support for USB")

Signed-off-by: Tim Harvey <tharvey@gateworks.com>