ide: add IDE_HFLAG_NO_ATAPI_DMA host flag

Add IDE_HFLAG_NO_ATAPI_DMA host flag and set it in host drivers which
don't support ATAPI DMA.  Then remove no longer needed hwif->atapi_dma.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/ide-dma.c b/drivers/ide/ide-dma.c
index bc57ce6..80b4f17 100644
--- a/drivers/ide/ide-dma.c
+++ b/drivers/ide/ide-dma.c
@@ -338,8 +338,10 @@
 	ide_hwif_t *hwif = drive->hwif;
 	struct hd_driveid *id = drive->id;
 
-	if (drive->media != ide_disk && hwif->atapi_dma == 0)
-		return 0;
+	if (drive->media != ide_disk) {
+		if (hwif->host_flags & IDE_HFLAG_NO_ATAPI_DMA)
+			return -1;
+	}
 
 	/*
 	 * Enable DMA on any drive that has
@@ -726,8 +728,10 @@
 	int x, i;
 	u8 mode = 0;
 
-	if (drive->media != ide_disk && hwif->atapi_dma == 0)
-		return 0;
+	if (drive->media != ide_disk) {
+		if (hwif->host_flags & IDE_HFLAG_NO_ATAPI_DMA)
+			return 0;
+	}
 
 	for (i = 0; i < ARRAY_SIZE(xfer_mode_bases); i++) {
 		if (req_mode < xfer_mode_bases[i])