Revert "msm: kgsl: Protect CP_STATE_DEBUG_INDEX"

This reverts commit c0611ccc22e440172924ed21437cb69ec9fcea55.
Revert "msm: kgsl: Mark the IOMMU setstate memory as read only"

This reverts commit 4fd319672de2e2f400b0820ffa95930051e85415.
Revert "msm: kgsl: Protect SMMU registers from being written by the GPU"

This reverts commit 86baf639f071996f80b6f05add8b8e0c05dadef0.
Revert "msm: kgsl: Enable protected mode for A3XX"

This reverts commit 3830f91388b3c57f037a9bdf97678d99db5ff0f3.