arm: omap4: panda: remove usb_nop_xceiv_register(v1)

Panda uses both twl6030 otg phy(vbus, id) and internal
phy(data lines, DP/DM), so removes usb_nop_xceiv_register to make
twl6030 otg driver working since current otg code only supports
one global transceiver. Otherwise, musb doesn't work without
the remove.

Reviewd-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>