graphics/spirv-cross: new port - required for games/lwjgl3

[vvd]

Summary

This port required for build lwjgl 3, and lwjgl 3 required for Java Minecraft Client 1.20.x run on FreeBSD without linux compatibility layer.

Tested build in poudriere and in live system 13.2-p10 amd64.
Also test build lwjgl 3.

Some details are here: https://github.com/LWJGL/lwjgl3/issues/421#issuecomment-1964114740

[arrowd]

Remember to add this port into graphics/Makefile

graphics/spirv-cross/pkg-plist

33

It is strange that the project installs .cmake files under DATADIR. I looked into CMakeLists.txt and it seems to be intentional.

[vvd]

graphics/spirv-cross/pkg-plist

33

Don't know why it need this.
I will change this in the future if necessary.