ARM: tegra: remove copy-and-pasted usb platform data from boards

trimslice and paz00 both have functionally identical platform
data for the tegra-ehci driver.  Move the platform data into
devices.c, and remove it from all the board files.

Signed-off-by: Colin Cross <ccross@android.com>
Tested-by: Konstantin Sinyuk <kostyas@compulab.co.il>
Acked-by: Olof Johansson <olof@lixom.net>