ARM: ux500: cut some platform data

This platform data is revoked: the drivers are getting the DMA
configuration from the device tree, it has been done like that
since the DMA support was merged and this data has not been used
since. The remaining auxdata is also unused.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>