So fix up the export in xfs_dir2.h that is needed by userspace.

<sigh>

Now xfs_dir3_sfe_put_ino has been made static. Revert 98f7462c ("xfs:
xfs_dir3_sfe_put_ino can be static") to being non static so that the
code shared with userspace is identical again.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>