Support DragonFly BSD

[mneumann]

The freebsd.patch did not apply cleanly as there is no longer a ifeq ($(PLATFORM),PLATFORM_DESKTOP) in raylib, at least in the current version I tried (vendor/raylib). Also, DragonFly still uses gcc and not clang.

[tjammer]

Is this needed specifically for dragonfly? I don't know too much about it

[mneumann]

No, this is only needed so that the patch applies cleanly. Maybe I have the wrong vendored raylib, but on my system the freebsd.patch fails to apply cleanly.

What is needed on DragonFly is to use "gcc" instead of "clang".

[tjammer]

Thanks for raising this PR.
It's a shame we cannot test any of this in CI, and I personally don't run BSD. I assume you've tested this on DragonFly, but do we know how the other BSDs are affected?

We used to get a FreeBSD build on opamci but this no longer works becaus the gl-depext is broken. I might need to install at least FreeBSD to test

[mneumann]

@tjammer we could set up CI for FreeBSD, OpenBSD, DragonFly etc. Other projects, e.g. solo5 do that as you can see here. https://github.com/Solo5/solo5/tree/main/.github/workflows

Maybe it makes sense to add CI before merging this PR!