msrtool: Add CS5536 probe and interrupt controller MSR definitions

[Peter Stuge]

I hope we'll get more insight into the ALIX situation with these.

//Peter

msrtool: Add CS5536 probe and interrupt controller MSR definitions

[Peter Stuge]

Peter Stuge wrote:
> msrtool: AMD CS5536 probe and definitions for the most important interrupt MSRs.

Here is an updated version of the patch with references cited in the
code and a few bug fixes; the 51400025 reset value was wrong and the
LPC bits had the wrong names.

//Peter