Tegra only supports, and always enables, device tree. Remove all ifdefs
and runtime checks for DT support from the driver. Platform data is
therefore no longer required. Rework the driver to parse the device tree
directly into struct sdhci_tegra.
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NChris Ball <cjb@laptop.org>