iommu: arm-smmu: Add support for ACTLR settings for sdm845

Some MMU500 implementations have additional settings in the ACTLR
register. Retrieve the settings from devicetree and validate that
all devices in the same iommu_group share the same ACTLR settings.

Change-Id: I108bac9bb63faf9ecda39295409ea5ff3d74bac3
Signed-off-by: Patrick Daly <pdaly@codeaurora.org>