[PATCH] powerpc: minor dart driver cleanup

Rpn is assigned every time in the loop, no need to increase it too.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

arch/powerpc/sysdev/dart_iommu.c

@@ -139,7 +139,6 @@ static void dart_build(struct iommu_table *tbl, long index,
 
 		*(dp++) = DARTMAP_VALID | (rpn & DARTMAP_RPNMASK);
 
-		rpn++;
 		uaddr += DART_PAGE_SIZE;
 	}