Change in coreboot[master]: drivers/intel/fsp/Makefile: error out when FSP files aren't specified

[Nico Huber (Code Review)]

Attention is currently required from: Furquan Shaikh, Tim Wawrzynczak, Andrey Petrov, Patrick Rudolph, Felix Held.
Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/57219 )

Change subject: drivers/intel/fsp/Makefile: error out when FSP files aren't specified
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Patch Set 5: Code-Review+1

(1 comment)

File src/drivers/intel/fsp2_0/Makefile.inc:

https://review.coreboot.org/c/coreboot/+/57219/comment/b0f7a8ce_724978b1 
PS5, Line 114: $(warning ADD_FSP_BINARIES isn't selected even though this SoC uses the FSP.)
             : $(warning The resulting image likely won't boot successfully.)
> There are a number of boards that do not select ADD_FSP_BINARIES in coreboot. […]

I'd say we want a warning but not like this. We already have such
warnings for a missing flash descriptor for instance. But that is
placed at the end of the build. I don't think a warning at the
start would get noticed.

Maybe just postpone this for another change.

Btw. when ADD_FSP_BINARIES is not selected that usually either means
one of two things: 1. the port is still WIP, 2. the binaries are not
publicly available. The former probably doesn't matter but a warning
shouldn't hurt. The latter I would prefer to not allow in our tree
at all.