USB: otg/ulpi.c : fix register write

ulpi_set_vbus and ulpi_set_flags are using ULPI_SET(register) to write
to the PHY's registers, which means we can only set bits in the PHY's
register and not clear them.
By directly using the address of the register without any offset, we
now get the expected behaviour for these functions.

Signed-off-by: Eric Bénard <eric@eukrea.com>
Cc: Daniel Mack <daniel@caiaq.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Sascha Hauer <kernel@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>