xfs: bump max fsgeom struct version

The latest version of the fs geometry structure is v5.  Bump this
constant so that xfs_db and mkfs calls to libxfs_fs_geometry will fill
out all the fields.

IOWs, this commit is a no-op for the kernel, but will be useful for
userspace reporting in later changes.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

fs/xfs/libxfs/xfs_sb.h

@@ -25,7 +25,7 @@ extern uint64_t	xfs_sb_version_to_features(struct xfs_sb *sbp);
 
 extern int	xfs_update_secondary_sbs(struct xfs_mount *mp);
 
-#define XFS_FS_GEOM_MAX_STRUCT_VER	(4)
+#define XFS_FS_GEOM_MAX_STRUCT_VER	(5)
 extern void	xfs_fs_geometry(struct xfs_mount *mp, struct xfs_fsop_geom *geo,
 				int struct_version);
 extern int	xfs_sb_read_secondary(struct xfs_mount *mp,