ARM: tegra: enable ums on nyan boards

This patch enables UMS on the nyan devices like the nyan-big.
A patch like this has been sent in by Stephen Warren some time ago for
other tegra devices: commit e6607cff.
But the nyan devices never received that functionality.

Signed-off-by: Tristan Bastian <tristan-c.bastian@gmx.de>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>