[S] Change in coreboot[main]: util/amdfwtool: Check for pkg-config presence

[Raul Rangel (Code Review)]

Attention is currently required from: Felix Held, Karthik Ramasubramanian, Martin Roth.

Raul Rangel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/78191?usp=email )

Change subject: util/amdfwtool: Check for pkg-config presence
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Patch Set 2:

(1 comment)

File util/amdfwtool/Makefile:

https://review.coreboot.org/c/coreboot/+/78191/comment/003c8e94_0726e318 :
PS1, Line 26: shell
> Done

Hrmm, I think it was failing because CFLAGS was lazily evaluated.

Changing flags to use the `:=` operator should make the `$(shell) evaluate eagerly so you can catch the error when it happens.

i.e.,
```
CFLAGS:=-O2 -Wall -Wextra -Wshadow ${WERROR}
```

See https://www.gnu.org/software/make/manual/html_node/Simple-Assignment.html