Change in coreboot[master]: Documentation: add Intel Broadwell

[Angel Pons (Code Review)]

Attention is currently required from:  Felix Singer, Paul Menzel, Iru Cai, Iru Cai (vimacs).
Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/54744 )

Change subject: Documentation: add Intel Broadwell
......................................................................

Patch Set 6: Code-Review+1

(1 comment)

File Documentation/soc/intel/broadwell/blobs.md:

https://review.coreboot.org/c/coreboot/+/54744/comment/65299d00_0c5f27bc 
PS6, Line 38: Broadwell SoC code doesn't support non-ULT Haswell or non-ULT Broadwell boards.
FWIW, I've tested Broadwell MRC.bin on the Asrock B85M Pro4 and it works properly. Of course, the code needs to be adapted and one needs to implement the things the Broadwell refcode blob does.