Change in coreboot[master]: lib/romstage_handoff.c: Initialize using a cbmem hook

[Julius Werner (Code Review)]

Attention is currently required from: Damien Zammit, Lee Leahy, Huang Jin, Arthur Heymans, Kyösti Mälkki, Andrey Petrov.
Julius Werner has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/52933 )

Change subject: lib/romstage_handoff.c: Initialize using a cbmem hook
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Patch Set 3:

(1 comment)

File src/lib/romstage_handoff.c:

https://review.coreboot.org/c/coreboot/+/52933/comment/8e22bb65_99b2196f 
PS3, Line 56: ROMSTAGE_CBMEM_INIT_HOOK(romstage_handoff_init);
Since this file is compiled unconditionally, adding an INIT_HOOK() expands this to a lot of platforms which never used it. Please add a Kconfig to limit compilation of the file to the right set of boards if you want to do this (I'm not quite sure what exactly this is or what the right set of boards for it would be, but I know the Arm boards I work on don't use this, for example).