iommu/tegra-smmu: Add PCI support

This patch simply adds support for PCI devices.

Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Tested-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20201125101013.14953-6-nicoleotsuka@gmail.com


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