Squashed revert of the mdp iommu fix:

commit 1d65ba0805a92b5674408d5c2f1044739072a8c7
Author: Sultanxda <sultanxda@gmail.com>
Date:   Wed Jun 11 16:02:09 2014 -0700

    Revert "mdp4_overlay: Fix graphical glitches caused by iommu mapping"

    This reverts commit 93feda4c3cb2b921d1786b042928bc79a3ddf38b.

commit 62641c131fb7de4f2529653e2d39001e5cd54462
Author: Sultanxda <sultanxda@gmail.com>
Date:   Wed Jun 11 16:01:56 2014 -0700

    Revert "mdp4_overlay: Make sure ion_map_iommu() is successful for all domains all the time"

    This reverts commit 056cce7cdbf3f0a46ab319e44b8a2c492d93d6ae.

commit be7ffda6b2308bd86b4cc3fdbf426d869cac9bb4
Author: Sultanxda <sultanxda@gmail.com>
Date:   Wed Jun 11 10:19:33 2014 -0700

    Revert "mdp4_overlay: Conditionally call ion_unmap_iommu()"

    This reverts commit 58f36c0011669ad2c44785314609d0a8f979be99.

commit 4d12cf7bb362e28760468c876d4222a9693c23db
Author: Sultanxda <sultanxda@gmail.com>
Date:   Wed Jun 11 10:19:07 2014 -0700

    Revert "gpu: ion: Don't issue kernel WARNING for iommu_map failure"

    This reverts commit 4b63eaf2bbf3ee3265fd7081fbff619fe1232a90.