The IDE Disk Controller driver has been extended to allow the secondary device on the channel to be initialised and used. A test as to whether this is working (for anyone interested) is to modify `init.cpp:87` to `auto dev_hd0 = IDEDiskDevice::create(IdeDiskDevice::DeviceType::SLAVE);`. The kernel will fail to boot, as there is no disk attached to CHANNEL 1's slave. This was born out of the fact that my FAT driver can't be tested as easily without creating a partition on `hda`.
Also run it across the whole tree to get everything using the One True Style.
We don't yet run this in an automated fashion as it's a little slow, but
there is a snippet to do so in makeall.sh.
