Feature/macos support

[SylphiaWindy]

Pull Request

Make OpenBOR compiling and working on macOS (again)

General Description

OpenBOR has dropped support for macOS for years officially. I found a very old post in the forum (https://www.chronocrash.com/forum/threads/mac-version-for-openbor.65/) talking about macOS port. I basically work everyday on a mac, and seems it is not that hard to make mac port possible(again).

Changes

• Updated envion.sh, assuming we are using homebrew to get libs for build dependency.
• Updated Makefile to use SDL2
• Updated Makefile to set arch for both x86_64(Intel Macs) and arm64(M1/M2 Macs)
• Updated Makefile, set some build options, such as removed -Werror
• Updated engine/openbor.c to get rid of "error: initializer element is not a compile-time constant"
• Updated engine/source/utils.c, not using mallinfo on macos, code from the post above.

How to compile

Tested on M1 mac (macOS 14.2.1 (23C71)) , and Intel mac (macOS 12.7.2 (21G1974))

• Install homebrew, XCode of course
• Install sdl2, sdl2_gfx, libvorbis, libogg, libpng by homebrew (maybe other libs but I did not recall)
• cd into openbor/engine, run build.sh 10
• copy your Paks into releases/DARWIN/OpenBOR.app/Contents/Resources/Paks

Remarks

• We will need an apple developer id for signing the compiled app if we want to publish it.
• It's OK to close this PR if you decide to not adding macOS support back.

[DCurrent]

Sorry @SylphiaWindy. I appreciate your work. In fact I will adapt some of what you did and credit you, but the last thing I want is another port to maintain, especially mac.

[SylphiaWindy]

It's okay, I do understand that the player base of mac system is too small, and it does increase the complexity of code maintenance.