ide: remove action argument in ide_do_drive_cmd

ide_do_drive_cmd is called only with ide_preempt action argument. So
we can remove the action argument in ide_do_drive_cmd and ide_action_t
typedef.

This patch also includes two minor cleanups: 1) ide_do_drive_cmd
always succeeds so we don't need the return value; 2) the callers use
blk_rq_init before ide_do_drive_cmd so there is no need to initialize
rq->errors.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/ide-floppy.c b/drivers/ide/ide-floppy.c
index 1852008..53209a4 100644
--- a/drivers/ide/ide-floppy.c
+++ b/drivers/ide/ide-floppy.c
@@ -291,7 +291,7 @@
 	rq->cmd_type = REQ_TYPE_SPECIAL;
 	rq->cmd_flags |= REQ_PREEMPT;
 	rq->rq_disk = floppy->disk;
-	(void) ide_do_drive_cmd(drive, rq, ide_preempt);
+	ide_do_drive_cmd(drive, rq);
 }
 
 static struct ide_atapi_pc *idefloppy_next_pc_storage(ide_drive_t *drive)