We need to explicitly mark words 85-87 as valid ones since
firmware doesn't do it.

This should fix support for LBA48 and FLUSH CACHE [EXT] command
which stopped working after we applied more strict checking of
identify words in:

	commit 942dcd85
	("ide: idedisk_supports_lba48() -> ata_id_lba48_enabled()")

and

	commit 4b58f17d
	("ide: ide_id_has_flush_cache() -> ata_id_flush_enabled()")
Reported-and-tested-by: N"Trevor Hemsley" <trevor.hemsley@ntlworld.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>