dt-bindings: iommu: qcom,iommu: Add QSMMUv2 and MSM8976 compatibles

Add compatible string "qcom,msm-iommu-v2" for the inner node,
along with "qcom,msm8976-iommu" as a first user of it and
"qcom,msm-iommu-v2-ns" and "qcom,msm-iommu-v2-sec" for the context
bank nodes to support Qualcomm's secure fw "SMMU v2" implementation.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230622092742.74819-6-angelogioacchino.delregno@collabora.com


Signed-off-by: Will Deacon <will@kernel.org>