libata-sff: separate out BMDMA irq handler

Separate out BMDMA irq handler from SFF irq handler.  The misnamed
host_intr() functions are renamed to ata_sff_port_intr() and
ata_bmdma_port_intr().  Common parts are factored into
__ata_sff_port_intr() and __ata_sff_interrupt() and used by sff and
bmdma interrupt routines.

All BMDMA drivers now use ata_bmdma_interrupt() or
ata_bmdma_port_intr() while all non-BMDMA SFF ones use
ata_sff_interrupt() or ata_sff_port_intr().

For now, ata_pci_sff_init_one() uses ata_bmdma_interrupt() as it's
used by both SFF and BMDMA drivers.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/ata/pata_scc.c b/drivers/ata/pata_scc.c
index fb318cd..d9db3f8 100644
--- a/drivers/ata/pata_scc.c
+++ b/drivers/ata/pata_scc.c
@@ -1105,7 +1105,7 @@
 	if (rc)
 		return rc;
 
-	return ata_host_activate(host, pdev->irq, ata_sff_interrupt,
+	return ata_host_activate(host, pdev->irq, ata_bmdma_interrupt,
 				 IRQF_SHARED, &scc_sht);
 }