freebsd-wifi-build: emulator builds now possible

[Adrian Chadd]

Hi,

I've just added a 'malta' target to my wifi build scripts. 'malta' is
a mips32 big-endian target for qemu-devel.

Steps:

* update your freebsd-wifi-build git tree
(http://github.com/freebsd/freebsd-wifi-build)
* grab the latest -head
* install qemu-devel
* (ensure that makefs is up to date on your box or the fullfsimage
pass won't work)
* /path/to/build malta buildworld buildkernel installworld
installkernel distribution fullroot fullfsimage
* dd if=/dev/zero of=../malta-swap.img bs=1k count=1 seek=1048576
* qemu-system-mips -M malta -kernel /tftpboot/kernel.MALTA -hda
../fullroot-malta.img -hdb ../swap-malta.img -nographic -m 256

It'll create a 4gig FS image and a 1gig swap file.

You can fire up dhclient in the emulator on le0 and get an IP address.
ping and non-socket things won't work as the default networking bridge
is a socket-based emulation - I haven't sat down to make the
tap+bridge version of it work.

The memory is specified by '-m 256'. Give smaller footprints a shot;
see what happens.

The swapfile is -hdb - I added that above so I could run a buildworld
inside the VM. You don't _need_ to use swap, but then building
software may be pretty amusing to watch.

I'm going to add mipsel next, then the 64 bit versions of the above.

My qemu VM is currently building world / kernel.