xfs: fix sb_meta_uuid usage

After changing the UUID on a v5 filesystem, xfstests fails
immediately on a debug kernel with:

XFS: Assertion failed: uuid_equal(&ip->i_d.di_uuid, &mp->m_sb.sb_uuid), file: fs/xfs/xfs_inode.c, line: 799

This needs to check against the sb_meta_uuid, not the user visible
UUID that was changed.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>