ide: make ide_hwif_t.ide_dma_{host_off,off_quietly} void (v2)

* since ide_hwif_t.ide_dma_{host_off,off_quietly} always return '0'
  make these functions void and while at it drop "ide_" prefix
* fix comment for __ide_dma_off_quietly()
* make __ide_dma_{host_off,off_quietly,off}() void and drop "__" prefix

v2:
* while at it rename atiixp_ide_dma_host_off() to atiixp_dma_host_off(),
  sgiioc4_ide_dma_{host_off,off_quietly}() to sgiioc4_dma_{host_off,off_quietly}()
  and sl82c105_ide_dma_off_quietly() to sl82c105_dma_off_quietly()
  [ Noticed by Sergei Shtylyov <sshtylyov@ru.mvista.com>. ]

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

diff --git a/drivers/ide/ide-floppy.c b/drivers/ide/ide-floppy.c
index 6196941..57cd21c 100644
--- a/drivers/ide/ide-floppy.c
+++ b/drivers/ide/ide-floppy.c
@@ -867,7 +867,7 @@
 	if (test_and_clear_bit(PC_DMA_IN_PROGRESS, &pc->flags)) {
 		printk(KERN_ERR "ide-floppy: The floppy wants to issue "
 			"more interrupts in DMA mode\n");
-		(void)__ide_dma_off(drive);
+		ide_dma_off(drive);
 		return ide_do_reset(drive);
 	}
 
@@ -1097,9 +1097,9 @@
 	pc->current_position = pc->buffer;
 	bcount.all = min(pc->request_transfer, 63 * 1024);
 
-	if (test_and_clear_bit(PC_DMA_ERROR, &pc->flags)) {
-		(void)__ide_dma_off(drive);
-	}
+	if (test_and_clear_bit(PC_DMA_ERROR, &pc->flags))
+		ide_dma_off(drive);
+
 	feature.all = 0;
 
 	if (test_bit(PC_DMA_RECOMMENDED, &pc->flags) && drive->using_dma)