Revert "iommu/arm-smmu: Convert to domain_alloc_paging()"

This reverts commit 9b3febc3 ("iommu/arm-smmu: Convert to
domain_alloc_paging()"). It breaks Qualcomm MSM8996 platform. Calling
arm_smmu_write_context_bank() from new codepath results in the platform
being reset because of the unclocked hardware access.

Fixes: 9b3febc3

 ("iommu/arm-smmu: Convert to domain_alloc_paging()")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/20240213-iommu-revert-domain-alloc-v1-1-325ff55dece4@linaro.org
Signed-off-by: Will Deacon <will@kernel.org>