arm/tegra: Prep boards for gpio/pinmux conversion to pdevs

The Tegra GPIO driver will be converted from static registration via
postcore_initcall() to be a platform device later in this patch series.
A new Tegra pinmux platform device will also be added.

Prepare for this by modifying all boards to register the appropriate
platform devices before-hand, so that when the drivers are converted,
those devices will be probed, and git bisectability will be maintained.

v2: Add resource definitions for GPIO and pinmux

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