usb: ulpi: Add omap-ulpi-view port support

usb: ulpi: Add omap-ulpi-view port support

Based on discussion from this thread [1].
Adding omap-view port that helps us in using the generic ulpi
framework for any ulpi phy ops using the INSNREG05_ULPI viewport
reg available on omap platform.

Currently ehci ports are available on omap3/4 platforms so enable the same
for beagle and panda, patch is tested on the same boards.

Thanks to Igor Grinberg <grinberg@compulab.co.il> for reviewing the
omap-ehci patches and suggesting this approach.

[1]: http://www.mail-archive.com/u-boot@lists.denx.de/msg76076.html

Tested-by: Stefano Babic <sbabic@denx.de>
Acked-by: Igor Grinberg <grinberg@compulab.co.il>
Signed-off-by: Govindraj.R <govindraj.raja@ti.com>