Fix for the OpenBMC 2.6 release

[Joseph Reynolds]

I would like to make a fix for the OpenBMC 2.6 release (branch=thud), 
that is https://github.com/openbmc/openbmc/tree/thud
The fix is the OpenBMC 2.6 version of this fix: 
https://gerrit.openbmc-project.xyz/c/openbmc/meta-phosphor/+/20393

Is there a process to get fixes into the 2.6 release?  My fix is in a 
meta-layer, so I follow the technical process here: 
https://github.com/openbmc/docs/blob/master/subtree.md.  Except how do I 
push my change into branch=thud?  (I am still a git novice.)

- Joseph