Currently the driver registers IOMMU bus operations for all busses even
if no ARM SMMU is present on a system. Depending on the driver probing
order this prevents the driver for the real IOMMU to register itself as
the bus-wide IOMMU.
Signed-off-by: NThierry Reding <treding@nvidia.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>