plat/linuxu: Adapt linuxu to new mrd fields

[mschlumpp]

Prerequisite checklist

• Read the contribution guidelines regarding submitting new changes to the project;
• Tested your changes against relevant architectures and platforms;
• Ran the checkpatch.uk on your commit series before opening this PR;
• Updated relevant documentation.

Base target

• Architecture(s): N/A
• Platform(s): linuxu
• Application(s): N/A

Additional configuration

Description of changes

The commit introducing the fields, did not update the linuxu platform causing a crash on boot.

[mschlumpp]

Given #1422 I think we can close this (except we want to have at least a bootable linuxu version in the history).
@skuenzer What do you think?

[skuenzer]

Given #1422 I think we can close this (except we want to have at least a bootable linuxu version in the history). @skuenzer What do you think?

Hi @mschlumpp, yes, this is true. #1422 got even merged in the meantime. I am closing this PR. But nevertheless thanks for your work.