sparc/iommu: fix ->map_sg return value

Just decrementing the sz value will lead to an incorrect return value.
Instead of just introducing a local variable switch to the standard
for_each_sg helper and standard naming of the arguments.

Fixes: ce65d36f3e ("sparc: remove the sparc32_dma_ops indirection")
Reported-by: Guenter Roeck <[email protected]>
Signed-off-by: Christoph Hellwig <[email protected]>
Acked-by: Sam Ravnborg <[email protected]>
1 file changed