usb: ulpi: Add Kconfig options for ULPI

The following options can be now enabled via defconfig:
- CONFIG_USB_ULPI
- CONFIG_USB_ULPI_VIEWPORT
- CONFIG_USB_ULPI_VIEWPORT_OMAP

Signed-off-by: Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Acked-by: Marek Vasut <marex@denx.de>