setup virtualbox for minix

Network is down in minix 3.1.2a when it is be installed in virtualbox. But it should work because the NIC of virtualbox is also AMD pcnet.

The template solution is:
1. set qemu_pci=1 in boot monitor, but what I do is to insert hard code to /usr/src/driver/pci/pci.c
2. comment line 631 in /usr/src/driver/lance.c ; it call assert(0), but I don;t know why assert(0) fails, but I think it;s not important. I don;t know why ec->linmem must be zero now, but what I need is network can work, and it does. So I don;t wanna to trace next codes.

what I learn in progress of solving this problem.
1. Linux has a good API in driver programming.
2.Minix's IPC make program more complicate, but u just trust on it, and focus on errors in lance driver.
3.Minix has command "service".
4.U must copy the execution file of driver to /usr/sbin, the Makefile in /usr/src/tools won;t do it for u.
5.virtualbox's chip id of NIC is 79C973, it's not easy to pronounce in Chinese. :)