The previous implementation of the PIIX3/4 PATA/IDE channel driver only
supported a single drive, as the object model was wrong (the channel
inherits the IRQ, not the disk drive itself). This fixes it by 'attaching'
two `PATADiskDevices` to a `PATAChannel`, which makes more sense.
The reading/writing code is presented as is, which violates the spec
outlined by Seagate in the linked datasheet. That spec is rather old,
so it might not be 100% up to date, though may cause issues on real
hardware, so until we can actually test it, this will suffice.
Also tweak the kernel's Makefile to use -nostdinc and -nostdinc++.
This prevents us from picking up random headers from ../Root, which may
include older versions of kernel headers.
Since we still need <initializer_list> for Vector, we specifically include
the necessary GCC path. This is a bit hackish but it works for now.
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`.
