If flush requests are being sent to the device we need to inherit the
failfast and driver-specific flags, too, otherwise I/O will fail.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>