Change in coreboot[master]: mb: remove duplicated Make code for spd.bin generation

[Felix Singer (Code Review)]

Felix Singer has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/44774 )

Change subject: mb: remove duplicated Make code for spd.bin generation
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Patch Set 5:

(1 comment)

https://review.coreboot.org/c/coreboot/+/44774/4//COMMIT_MSG 
Commit Message:

https://review.coreboot.org/c/coreboot/+/44774/4//COMMIT_MSG@9 
PS4, Line 9: Drop duplicated code for spd.bin generation that is provided globally
           : in lib/Makefile.inc.
> grep -ri spd src/mainboard ;; IMO that is so obvious that there is no need to document this

With `grep -ri spd src/mainboard` I get a lot of false-positives too. Using `grep -r "SPD_BIN"` I found some more.

./google/rambi/variants/ninja/Makefile.inc
./intel/cannonlake_rvp/spd/Makefile.inc
./intel/icelake_rvp/spd/Makefile.inc
./intel/jasperlake_rvp/spd/Makefile.inc
./intel/kblrvp/spd/Makefile.inc
./razer/blade_stealth_kbl/spd/Makefile.inc