iommu/arm-smmu: Reorganize arm_smmu_domain_add_master()

Make arm_smmu_domain_add_master() not use the smmu_domain to detect the
s2cr configuration, instead pass it in as a parameter. It always returns
zero so make it return void.

Since it no longer really does anything to do with a domain call it
arm_smmu_master_install_s2crs().

This is done to make the next two patches able to re-use this code without
forcing the creation of a struct arm_smmu_domain.

Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/1-v2-c86cc8c2230e+160bb-smmu_newapi_jgg@nvidia.com
Signed-off-by: Will Deacon <will@kernel.org>