GXemul Code2

Inspired by Luchezar Georgiev's patch for subu_cio, a closer look at the subu borrow bit resulted in a bug fix which finally allows a OpenBSD/luna88k 6.8 ramdisk to boot all the way to userland. :-)

Link to wikipedia article on the 88K architecture.

Now, the OpenBSD website says that 6.7 was the last SGI release, not 6.5.

Adding a patch from Luchezar Georgiev for missing variant of ot for 88100 (immediate argument), and for missing addu_cio and subu_cio instructions.

Copyright year update.

Include ASID and VPN2 in MIPS load/store misalignment exceptions (patch from Nick Hudson).

Add comment about checking R10000 specifics.

Adding stdio.h include, required for build with some gcc versions on Linux. Noticed by Michael Mikonos.

Minihack to allow reading the bootloader from IRIX formatted disk, NetBSD install CDROM, and OpenBSD install CDROM.

SGI boot / partition work-in-progress.