powerpc/powernv/ioda2: Rework iommu_table creation
powerpc/powernv/ioda2: Rework iommu_table creation

This moves iommu_table creation to the beginning to make following changes
easier to review. This starts using table parameters from the iommu_table
struct.

This should cause no behavioural change.

Signed-off-by: Alexey Kardashevskiy <ac1fc56530d7d037e1ea666f130daca22d72f964@ozlabs.ru>
Reviewed-by: David Gibson <aa743a0aaec8f7d7a1f01442503957f4d7a2d634@gibson.dropbear.id.au>
Reviewed-by: Gavin Shan <0398910e4f4970259b451f0f9d0686cc5e961b81@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <864f124608374e06e4da1fa5d2e47ed839b95411@ellerman.id.au>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs