Merge tag 'tegra-for-4.7-gm20b' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux into next/dt64

Merge "arm64: tegra: Enable GM20B GPU on Tegra210" from Thierry Reding:

Complement the GM20B GPU device tree node on Tegra210 with missing
properties to make it usable.

* tag 'tegra-for-4.7-gm20b' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux:
  arm64: tegra: Add IOMMU node to GM20B on Tegra210
  arm64: tegra: Add reference clock to GM20B on Tegra210
  dt-bindings: Add documentation for GM20B GPU
  dt-bindings: gk20a: Document iommus property
  dt-bindings: gk20a: Fix typo in compatible name