[PATCH] powerpc: tidy up iseries/pci.c

Remove some unused counters.

No need to allocate iomm_table and iobar_table, which means that
iomm_table_initialize is not longer needed.

Use kzalloc where sensible.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>