Tegra platform support

Hi,

This is for the most part a repost of the arch/arm/mach-tegra parts of
Erik Gilling's post of the Tegra series from April 13. I've done some
minor cleanups and picked up a couple of bugfixes from later patches,
but I wanted to keep the original series bite size for easier review.

There is more to come once this is in.

Russell, do you prefer to take the initial series and feed it to Linus, or
should I send a direct pull request with your acked-by (once you give it)?


Thanks,

-Olof