[POWERPC] Move allocation of cell IOMMU pad page

There's no need to allocate the pad page unless we're going to actually
use it - so move the allocation to where we know we're going to use it.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
1 file changed