You need to fetch a recent version from git. One that includes
https://github.com/koreader/koreader...b74c7961fa71e2 (merged yesterday).
Then (and with the rest of build prerrequisites) you should be able to build the emulator on your device.
Once you're able to build the emulator have a look at how the debian target is built. You can repurpose 99% of it to build a generic linux target.
Packaging an emulator for whatever distro is not a good idea as the emulator exposes some features not available in different platforms and lacks proper info for some stuff, like config paths.