[coreboot-gerrit] Change in coreboot[master]: vboot: use cbfstool truncate

[build bot (Jenkins) (Code Review)]

build bot (Jenkins) has posted comments on this change. ( https://review.coreboot.org/21609 )

Change subject: vboot: use cbfstool truncate
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Patch Set 1: Verified+1

Build Successful

https://qa.coreboot.org/job/coreboot-gerrit/60802/ : SUCCESS

https://qa.coreboot.org/job/coreboot-checkpatch/15988/ : SUCCESS