libata-sff: ata_sff_[dumb_]qc_prep are BMDMA specific

Both qc_prep functions deal only with BMDMA PRD setup and PIO only SFF
drivers don't need them.  Rename to ata_bmdma_[dumb_]qc_prep() and
relocate.

All usages are renamed except for pdc_adma and sata_qstor.  Those two
drivers are not BMDMA drivers and don't need to call BMDMA qc_prep
functions.  Calls to ata_sff_qc_prep() in the two drivers are removed.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/ata/sata_nv.c b/drivers/ata/sata_nv.c
index 64e9982..7a283d5 100644
--- a/drivers/ata/sata_nv.c
+++ b/drivers/ata/sata_nv.c
@@ -1409,7 +1409,7 @@
 		BUG_ON(!(pp->flags & NV_ADMA_ATAPI_SETUP_COMPLETE) &&
 			(qc->flags & ATA_QCFLAG_DMAMAP));
 		nv_adma_register_mode(qc->ap);
-		ata_sff_qc_prep(qc);
+		ata_bmdma_qc_prep(qc);
 		return;
 	}
 
@@ -2012,7 +2012,7 @@
 static void nv_swncq_qc_prep(struct ata_queued_cmd *qc)
 {
 	if (qc->tf.protocol != ATA_PROT_NCQ) {
-		ata_sff_qc_prep(qc);
+		ata_bmdma_qc_prep(qc);
 		return;
 	}