[coreboot] proposed patch, notsigned off, comments welcome.

[ron minnich]

This is a first try at a program to grok lxirqs.

Sanity check first, I'm not signing this off yet. Are the enable and
invert tests correct below?

Long term goal is a program that will follow the IRQ through the magic
rabbit hole and up
to the CPU. I don't know how to do vr reads in user mode, however.

Here's the current output on alix1c, which is strange looking to me.
IRQ A, GPIO pin 0
Input Enabled and Not Inverted
IRQ B, GPIO pin 7
Input Enabled and Inverted
IRQ C, GPIO pin 12
Input Enabled and Inverted
IRQ D, GPIO pin 13
Input Disabled and Not Inverted