btrfs: rename EXTENT_BUFFER_NO_CHECK to EXTENT_BUFFER_ZONED_ZEROOUT

EXTENT_BUFFER_ZONED_ZEROOUT better describes the state of the extent buffer,
namely it is written as all zeros. This is needed in zoned mode, to
preserve I/O ordering.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>