bin/41155: recent mtree ordering breaks systat/sysstat installation uid/gid/perms

[njoly%pasteur.fr@localhost]

>Number:         41155
>Category:       bin
>Synopsis:       recent mtree ordering breaks systat/sysstat installation 
>uid/gid/perms
>Confidential:   no
>Severity:       serious
>Priority:       low
>Responsible:    bin-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Apr 05 22:20:00 +0000 2009
>Originator:     Nicolas Joly
>Release:        NetBSD 5.99.10
>Organization:
Institut Pasteur
>Environment:
System: NetBSD nicodeme.sis.pasteur.fr 5.99.10 NetBSD 5.99.10 (NICODEME) #1: 
Sun Apr 5 16:13:00 CEST 2009 
njoly%nicodeme.sis.pasteur.fr@localhost:/local/src/NetBSD/obj.amd64/sys/arch/amd64/compile/NICODEME
 amd64
Architecture: x86_64
Machine: amd64
>Description:
After upgrading one of my -current machine, i noticed that systat(1) won't
start anymore due to permission problem ...

njoly@lanfeust [~]> systat 
/dev/mem: Permission denied
njoly@lanfeust [~]> sysstat 
/dev/mem: Permission denied

It looks like that with recent mtree modification to do list ordering, now
sysstat(1) link get installed before systat(1) which has the expected
uid/gid/perms.

from an old working alpha base.tgz:
njoly@thanos [binary/sets]> tar tvzf base.tgz | grep -e systat -e sysstat
-r-xr-sr-x  1 root     kmem      160887 Mar 13 16:15 ./usr/bin/systat
-r-xr-xr-x  2 root     wheel          0 Mar 13 16:15 ./usr/bin/sysstat == 
./usr/bin/systat

from a new broken amd64 base.tgz:
njoly@lanfeust [binary/sets]> tar tvzf base.tgz | grep -e systat -e sysstat
-r-xr-xr-x  1 root     wheel     134230 Apr  5 19:04 ./usr/bin/sysstat
-r-xr-sr-x  2 root     kmem           0 Apr  5 19:04 ./usr/bin/systat == 
./usr/bin/sysstat

>How-To-Repeat:
try to install/update -current from sets. Notice that systat won't work
anymore due to permission problem.
>Fix: