iommu/arm-smmu-v3: Pass in cmdq pointer to arm_smmu_cmdq_init

So that this function can be used by other cmdqs than &smmu->cmdq only.

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Link: https://lore.kernel.org/r/e11a3c0bde172c9652c2946f12bc2ceed4c3a355.1724970714.git.nicolinc@nvidia.com


Signed-off-by: Will Deacon <will@kernel.org>