The procedure is:
1. remove runebase from /sys/src/libc/port/mkfile
2. cd /sys/src/libc && mk install && mk clean
3. for(i in /sys/src/cmd/8?) {cd $i && mk install && mk clean}
4. add runebase in /sys/src/libc/port/mkfile
5. cd /sys/src/libc && mk install && mk clean
6. cd /sys/src && mk install && mk clean-- David du Colombier
