Add link directives for iOS frameworks

[michaelfairley]

These frameworks are necessary to link SDL2 into an iOS program.
https://github.com/spurious/SDL-mirror/blob/a4a9743a983dfccd6e7cc16fa3cb0f6d468041c1/configure.in#L3524-L3533

[Cobrand]

Build is failing on nightly but it looks like it's linked to #686.

If you could re-order those statements so that it's in the same order as the original SDL2 file, that would be great.
Also, why did you omit the equivalent of the EXTRA_LDFLAGS="$EXTRA_LDFLAGS -Wl,-framework,Foundation" line?

As a side note, it would be interesting to have a tutorial in this repo that would explain how to setup a simple game in SDL2 from scratch on both Android and iOS.
I think people would be genuinely interested by that, as I've seen multiple PRs related to Android as well lately. (just a wild thought, not targeted at you or anything)

[michaelfairley]

Ah! I had originally copied the list out of the 2.0.5 source, but it's since been reordered and tweaked on master (which is what I linked you to). I've updated this PR to reflect master.

I'm actually in the process of (very slowly) trying to put together a "build your game for Mac/Win/Linux/iOS/Android/Emscripten" tutorial/demo/toolset thing. Unfortunately, Android and iOS are both wayyyy more complex than mac/win/linux (a bunch of different architectures, simulator vs device, the fact that there aren't precompiled binaries, SDL wanting to provide the main method, etc etc etc), even a simple tutorial ends up being pretty involved.

[Cobrand]

I would be very interested to share that tutorial of yours from this repo. Please tell me if you need any help/assistance or preemptive feedback for that demo, I'm always happy to help!