[coreboot] [patch] x11ssh-f hanging in fsp, probably IGD init

[Valentin Kleibel]

Hi,

After some failures i was successful booting coreboot on a supermicro 
x11ssh-f [CPU: Xeon E3-1220 v5].
Built from the most recent git coreboot hangs indefinitely at:
> [DEBUG]  BS: BS_DEV_INIT_CHIPS entry times (exec / console): 283 / 381 ms
> [DEBUG]  IA32_FEATURE_CONTROL status: locked
> [INFO ]  POST: 0x71
> [DEBUG]  WEAK: src/soc/intel/skylake/chip.c/mainboard_silicon_init_params called
> [ERROR]  Null dereference at eip: 0x7f317e15
> [INFO ]  POST: 0x93

We noticed the proposed change 
https://review.coreboot.org/c/coreboot/+/51332 from over a year ago and 
updated the patch.
The attached igd_disabled.patch applies cleanly on the current tree and 
built with the attached config the board boots as expected incl. video 
out via AST2400. (This was our final config, previous tests were done 
without mecleaner)

Maybe this helps someone to get coreboot running or a fix could be 
applied upstream.

Cheers,
Valentin