how does qemu generate the path from 60-edk2-x86_64.json?

[daggs]

Greetings,

I was wondering how qemu generates the path for edk2-x86_64-code.fd from from 
60-edk2-x86_64.json
the file contains this: "filename": "share/qemu/edk2-x86_64-code.fd",
however the real path is /usr/share/qemu/edk2-x86_64-code.fd.

where does the /usr prefix comes?
the reason I'm asking is because I have two servers with the same version 
(5.2.0), both running gentoo.
when I'm trying to boot an uefi guest on one, it works, but on the other I'm 
getting this error:
error: Path 'share/qemu/edk2-x86_64-secure-code.fd' is not accessible: No such 
file or directory
if I change the path to /usr/share/qemu/edk2-x86_64-code.fd in 
edk2-x86_64-code.fd, the vm boots again,

I've found this https://bugs.gentoo.org/766743 however I'd assume this will 
happen every time or when it happens nothing will depend on /usr

any ideas?

Thanks,

Dagg.