Change in coreboot[master]: payloads: Add LinuxBoot payload in u-root mode

[build bot (Jenkins) (Code Review)]

build bot (Jenkins) has posted comments on this change. ( https://review.coreboot.org/23071 )

Change subject: payloads: Add LinuxBoot payload in u-root mode
......................................................................

Patch Set 12:

Build Failed

https://qa.coreboot.org/job/coreboot-gerrit/67531/ : FAILURE

https://qa.coreboot.org/job/coreboot-checkpatch/22058/ : SUCCESS