Move the abstract in-memory version of various btree block headers
out of xfs_da_format.h as they aren't on-disk formats.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>