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-cd.c b/drivers/ide/ide-cd.c
index 624d488..45a928c 100644
--- a/drivers/ide/ide-cd.c
+++ b/drivers/ide/ide-cd.c
@@ -1104,7 +1104,7 @@
 	if (dma) {
 		info->dma = 0;
 		if ((dma_error = HWIF(drive)->ide_dma_end(drive)))
-			__ide_dma_off(drive);
+			ide_dma_off(drive);
 	}
 
 	if (cdrom_decode_status(drive, 0, &stat))
@@ -1700,7 +1700,7 @@
 	if (dma) {
 		if (dma_error) {
 			printk(KERN_ERR "ide-cd: dma error\n");
-			__ide_dma_off(drive);
+			ide_dma_off(drive);
 			return ide_error(drive, "dma error", stat);
 		}
 
@@ -1826,7 +1826,7 @@
 		info->dma = 0;
 		if ((dma_error = HWIF(drive)->ide_dma_end(drive))) {
 			printk(KERN_ERR "ide-cd: write dma error\n");
-			__ide_dma_off(drive);
+			ide_dma_off(drive);
 		}
 	}