This one was a little fiddly in the sense that it depends on a number of submodules, but I worked it out using multiple sources. There are no versioned releases for these, so I had to use specific commits, but I used those referenced in the PPSSPP repository at version 1.2.2 (latest versioned release). I know that it's often preferred to use that very latest builds of PPSSPP, but I figure it's probably best that we stick with the stable releases since we can't really provide nightly builds in the first place.
I also couldn't get the git versioning to work, so I just used sed to patch unknown to 1.2.2 to avoid having it say unknown everywhere. If somebody else wants to try to fix that, go for it; it would report that it found git and print the version, but then say it couldn't find git immediately afterwards and give up on it, so there you go. Probably my fault somehow. ._.