iommu-updates-v4.3

This time the IOMMU updates are mostly cleanups or fixes. No big new
features or drivers this time. In particular the changes include:

	* Bigger cleanup of the Domain<->IOMMU data structures and the
	  code that manages them in the Intel VT-d driver. This makes
	  the code easier to understand and maintain, and also easier to
	  keep the data structures in sync. It is also a preparation
	  step to make use of default domains from the IOMMU core in the
	  Intel VT-d driver.

	* Fixes for a couple of DMA-API misuses in ARM IOMMU drivers,
	  namely in the ARM and Tegra SMMU drivers.

	* Fix for a potential buffer overflow in the OMAP iommu driver's
	  debug code

	* A couple of smaller fixes and cleanups in various drivers

	* One small new feature: Report domain-id usage in the Intel
	  VT-d driver to easier detect bugs where these are leaked.