ARM: ux500: Add Device Tree nodes for the ux500 Crypt device

This patch provides information required to setup ux500-crypt when
booting with DT on the Snowball low-cost development platform.

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>