ARM: ux500: Populate the ux500-musb Device Tree entry

This patch provides all the information to successfully probe() and
correctly configure the ux500-musb device driver for DMA.

Acked-by: Fabio Baltieri <fabio.baltieri@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>