Hello!
/ - is root of package build directory
The efivar package creates file `/src/include/efivar/efivar-guids.h`. The package must install all files from `/src/include/efivar/` (you can find them in `/usr/include/efivar` after installing package) but I can't find the efivar-guids.h. It exists in build directory but it doesn't exist in system after installing. I don't know why...