[coreboot-gerrit] Change in coreboot[master]: arch/x86: Add a common romstage entry

[Paul Menzel (Code Review)]

Attention is currently required from: Jason Glenesk, Raul Rangel, Furquan Shaikh, Marshall Dawson, Arthur Heymans, Patrick Rudolph, Felix Held.
Paul Menzel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/55067 )

Change subject: arch/x86: Add a common romstage entry
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Patch Set 1:

(1 comment)

Patchset:

PS1: 
CC         bootblock/lib/prog_loaders.o
    src/lib/prog_loaders.c:19:10: fatal error: romstage_common.h: No such file or directory
     #include <romstage_common.h>
              ^~~~~~~~~~~~~~~~~~~
    compilation terminated.