https://github.com/openwrt/openwrt/pull/1968 hasn't been updated lately and has two files that are conflicting. I believe I've sorted out the conflicts. However, this pull request isn't mine and I've no idea how to merge in these changes. Anyone able to help me?
Caveats: I'm not a programmer. I have almost zero experience with github. I have even less experience with Linux. The fact I was able to update these files and successfully build is a bigger surprise to me than to you. 
uxgood is pretty active in keeping it up to date... , updates it every x comment / month or so... as the pr has been sitting there for donkeys years... the incentive to keep returning and updating it diminishes exponentially.
you can click the files tab near the top > click + next to the line number > click the +/- icon in the editor ( insert suggestion ) but i'm pretty sure they'll be fine in working it out on their own...
in which case, you'll have to keep your "local commit diff" until they get the chance / incentive. ( you can post your patch in "< / >" tags below also... because there are likely others who may need it, as UEFI support generates significant interest )
Well anyway my first try was... less than successful 
but I'm a lot closer now. See this post for details.
Side Note, I tried tagging it with @uxgood but that isn't the right user name. Any idea what is the right user name?
uxgood did update the pull request. I used it to create a UEFI (efi) build and successfully installed it on a ODROID-H2. No merge conflicts.