iommu/arm-smmu-v3: Keep track of arm_smmu_master_domain for SVA

iommu/arm-smmu-v3: Keep track of arm_smmu_master_domain for SVA

Fill in the smmu_domain->devices list in the new struct arm_smmu_domain
that SVA allocates. Keep track of every SSID and master that is using the
domain reusing the logic for the RID attach.

This is the first step to making the SVA invalidation follow the same
design as S1/S2 invalidation. At present nothing will read this list.

Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/9-v9-5cd718286059+79186-smmuv3_newapi_p2b_jgg@nvidia.com
Signed-off-by: Will Deacon <will@kernel.org>