ide: add ->pc_{update,io}_buffers methods

Add ->pc_{update,io}_buffers methods to ide_drive_t and use
them instead of {update,io}_buffers ide_pc_intr() arguments.

There should be no functional changes caused by this patch.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/scsi/ide-scsi.c b/drivers/scsi/ide-scsi.c
index ff2b199..b4ba404 100644
--- a/drivers/scsi/ide-scsi.c
+++ b/drivers/scsi/ide-scsi.c
@@ -275,7 +275,7 @@
  */
 static ide_startstop_t idescsi_pc_intr (ide_drive_t *drive)
 {
-	return ide_pc_intr(drive, idescsi_pc_intr, NULL, ide_io_buffers);
+	return ide_pc_intr(drive, idescsi_pc_intr);
 }
 
 static ide_startstop_t idescsi_transfer_pc(ide_drive_t *drive)
@@ -407,7 +407,9 @@
 	set_bit(IDESCSI_LOG_CMD, &scsi->log);
 #endif /* IDESCSI_DEBUG_LOG */
 
-	drive->pc_callback = ide_scsi_callback;
+	drive->pc_callback	 = ide_scsi_callback;
+	drive->pc_update_buffers = NULL;
+	drive->pc_io_buffers	 = ide_io_buffers;
 
 	ide_proc_register_driver(drive, scsi->driver);
 }