xfs_repair: remove unused fs_sb_feature_bits_allowed fs_sb_feature_bits_allowed is never set to anything but 1; remove it and all associated code. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Eric Sandeen <sandeen@sandeen.net>