ARM: tegra: harmony: Set WM8903 gpio_base

This is the final patch to enable audio support on Harmony. It additionally
relies on the latest ASoC branch being merged in, which provides the header
defining the gpio_base field in the WM8903 platform data.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Olof Johansson <olof@lixom.net>