[S] Change in coreboot[main]: Makefile.mk: Skip unnecessary recompiles when static.c is updated

[Nico Huber (Code Review)]

Attention is currently required from: Nicholas Chin.

Nico Huber has posted comments on this change by Nicholas Chin. ( https://review.coreboot.org/c/coreboot/+/84387?usp=email )

Change subject: Makefile.mk: Skip unnecessary recompiles when static.c is updated
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Patch Set 2: Code-Review+1

(3 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/84387/comment/cd6d3886_52310698?usp... :
PS2, Line 21: a 
spurious `a`

https://review.coreboot.org/c/coreboot/+/84387/comment/0bfd638c_e46ff267?usp... :
PS2, Line 21: make static.c a an order-only prerequisite
`static.h`, isn't it?

https://review.coreboot.org/c/coreboot/+/84387/comment/1b023468_ef7c7e3f?usp... :
PS2, Line 37: i440f
i440f*x*