scripts/upd-instroot does the following:

    (cd $p/bin; find) | (cd $p/bin; /bin/cpio --quiet -pdmu $p/usr/bin)
    (cd $p/sbin; find) | (cd $p/sbin; /bin/cpio --quiet -pdmu $p/usr/sbin)

moving everything from /sbin to /usr/sbin will break any relative symlinks into
/bin or /sbin.. like /usr/bin/udevinfo (which is how HAL discovers devices):
    /usr/bin/udevinfo -> ../../sbin/udevadm
(this was changed 5 days ago for bug #432878)

A simple hack to work around this would be to do:
    ln -sf /sbin/udevadm $p/usr/bin/udevinfo
since we have udev in stage1 these days. On the other hand, here's a bash script
that should fix up the links:

    # Fix relative links like /usr/bin/udevinfo -> ../../sbin/udevadm
    for brokenlink in $(find $p/usr/{bin,sbin} -follow -lname '*'); do
        target="$(readlink $brokenlink)"
        for pathbit in bin sbin; do
            # if it starts with "../../sbin/", remove that
            newtarget="${target##../../$pathbit/}"
            # if we removed something, replace it with the proper path
            if [ "$newtarget" != "$target" ]; then
                # make it ../sbin/ instead
                ln -sf "../$pathbit/$newtarget" "$brokenlink"
            fi
        done
    done