[SCSI] More buffer->request_buffer changes

Seem like quite a few splipped through the cracks.  Here's a patch to
update all references I could find:

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/drivers/scsi/qlogicpti.c b/drivers/scsi/qlogicpti.c
index 69e0551..5b2f074 100644
--- a/drivers/scsi/qlogicpti.c
+++ b/drivers/scsi/qlogicpti.c
@@ -874,7 +874,7 @@
 	if (Cmnd->use_sg) {
 		int sg_count;
 
-		sg = (struct scatterlist *) Cmnd->buffer;
+		sg = (struct scatterlist *) Cmnd->request_buffer;
 		sg_count = sbus_map_sg(qpti->sdev, sg, Cmnd->use_sg, Cmnd->sc_data_direction);
 
 		ds = cmd->dataseg;
@@ -1278,7 +1278,7 @@
 
 		if (Cmnd->use_sg) {
 			sbus_unmap_sg(qpti->sdev,
-				      (struct scatterlist *)Cmnd->buffer,
+				      (struct scatterlist *)Cmnd->request_buffer,
 				      Cmnd->use_sg,
 				      Cmnd->sc_data_direction);
 		} else {