ide: fix IDE_HFLAG_NO_ATAPI_DMA handling in config_drive_for_dma()

commit 33c1002ed912ac9dacedd5d5b166da3b72d18460 incorrectly changed return value from '0' to '-1', fix it (ns87415 was the only host driver affected since it uses both IDE_HFLAG_TRUST_BIOS_FOR_DMA and IDE_HFLAG_NO_ATAPI_DMA).

---
 drivers/ide/ide-dma.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: b/drivers/ide/ide-dma.c
===================================================================
@@ -340,7 +340,7 @@ static int config_drive_for_dma (ide_dri
 
 	if (drive->media != ide_disk) {
 		if (hwif->host_flags & IDE_HFLAG_NO_ATAPI_DMA)
-			return -1;
+			return 0;
 	}
 
 	/*