ide: add IDE_HFLAG_BOOTABLE host flag

Add IDE_HFLAG_BOOTABLE host flag and IDE_HFLAG_OFF_BOARD define.  Convert
all host drivers using ide_pci_device_t to use IDE_HFLAG_{BOOTABLE,OFF_BOARD}
instead of d->bootable and then remove no longer needed d->bootable.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/pci/cs5535.c b/drivers/ide/pci/cs5535.c
index 45dc9a1..a93ba9a 100644
--- a/drivers/ide/pci/cs5535.c
+++ b/drivers/ide/pci/cs5535.c
@@ -195,8 +195,8 @@
 	.name		= "CS5535",
 	.init_hwif	= init_hwif_cs5535,
 	.autodma	= AUTODMA,
-	.bootable	= ON_BOARD,
-	.host_flags	= IDE_HFLAG_SINGLE | IDE_HFLAG_POST_SET_MODE,
+	.host_flags	= IDE_HFLAG_SINGLE | IDE_HFLAG_POST_SET_MODE |
+			  IDE_HFLAG_BOOTABLE,
 	.pio_mask	= ATA_PIO4,
 };