powerpc/pseries: Pass phb only to iommu_table_setparms_lpar

iommu_table_setparms_lpar needs either the phb or the subbusnumber
(not both), pass the phb to make it similar to iommu_table_setparms.

Note: In cases where a caller was passing bus->number previously to
iommu_table_setparms_lpar() rather than phb->bus->number, this can lead
to a different value in tbl->it_busno. The only example of this was the
removed pci_dma_dev_setup_pSeriesLP(), removed in "ppc/iommu: remove
unneeded pci_dma_dev_setup_pSeriesLP".

[BenH: You updated only one of the two callers. Fixed that for you]

Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>