powerpc/cell: Fix cell iommu after it_page_shift changes

The patch to add it_page_shift incorrectly changed the increment of
uaddr to use it_page_shift, rather then (1 << it_page_shift).

This broke booting on at least some Cell blades, as the iommu was
basically non-functional.

Fixes: 3a553170d35d ("powerpc/iommu: Add it_page_shift field to determine iommu page size")
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/platforms/cell/iommu.c

@@ -197,7 +197,7 @@ static int tce_build_cell(struct iommu_table *tbl, long index, long npages,
 
 	io_pte = (unsigned long *)tbl->it_base + (index - tbl->it_offset);
 
-	for (i = 0; i < npages; i++, uaddr += tbl->it_page_shift)
+	for (i = 0; i < npages; i++, uaddr += (1 << tbl->it_page_shift))
 		io_pte[i] = base_pte | (__pa(uaddr) & CBE_IOPTE_RPN_Mask);
 
 	mb();