omap3logic: Fix PBIAS Bug

The PBIAS fixing is done in the MMC driver, and doing it in the
the board file conflicts with the driver causing intermittent
hangs on reboot.  Remove this from the board file and let
the driver do it.

Signed-off-by: Adam Ford <aford173@gmail.com>
Reviewed-by: Tom Rini <trini@konsulko.com>