[coreboot-gerrit] Change in coreboot[master]: util/docker: Replace all variables in Dockerfile

[Angel Pons (Code Review)]

Attention is currently required from: Martin Roth, Marshall Dawson.
Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/47339 )

Change subject: util/docker: Replace all variables in Dockerfile
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Patch Set 1: Code-Review+2