iommu/arm-smmu: Add global/context fault implementation hooks

Add global/context fault hooks to allow vendor specific implementations
override default fault interrupt handlers.

Update NVIDIA implementation to override the default global/context fault
interrupt handlers and handle interrupts across the two ARM MMU-500s that
are programmed identically.

Signed-off-by: Krishna Reddy <vdumpa@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Nicolin Chen <nicoleotsuka@gmail.com>
Reviewed-by: Pritesh Raithatha <praithatha@nvidia.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Thierry Reding <thierry.reding@gmail.com>
Link: https://lore.kernel.org/r/20200718193457.30046-6-vdumpa@nvidia.com
Signed-off-by: Will Deacon <will@kernel.org>