[ARM] ARM SCSI: Don't try to dma_map_sg too many scatterlist entries

An off-by-one bug meant we were always trying to map one too many
scatterlist entries.  This was mostly harmless prior to the checks
going in to consistent_sync(), but now causes the kernel to BUG.

Also, powertec.c was missing an assignment to info->ec.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/scsi/arm/cumana_2.c b/drivers/scsi/arm/cumana_2.c
index d2d51dc..82add77 100644
--- a/drivers/scsi/arm/cumana_2.c
+++ b/drivers/scsi/arm/cumana_2.c
@@ -178,10 +178,10 @@
 			dma_dir = DMA_MODE_READ,
 			alatch_dir = ALATCH_DMA_IN;
 
-		dma_map_sg(dev, info->sg, bufs + 1, map_dir);
+		dma_map_sg(dev, info->sg, bufs, map_dir);
 
 		disable_dma(dmach);
-		set_dma_sg(dmach, info->sg, bufs + 1);
+		set_dma_sg(dmach, info->sg, bufs);
 		writeb(alatch_dir, info->base + CUMANASCSI2_ALATCH);
 		set_dma_mode(dmach, dma_dir);
 		enable_dma(dmach);