uboot-imx

omap3: igep00x0: Remove USB support due DM_USB deadline

The USB support for this board was never really tested, in fact, the
presence of these options are more a copy & paste error from the
Beagleboard than a feature that really was used. As doesn't work, remove
for now. If someone at some point want to add this support he'll need to
migrate the board to use CONFIG_DM_USB instead.

Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>