Update Xcode project file and SDL1 in oslibs/macosx

[BenderBlog]

Main change:

1. Update Xcode to latest, remove tons of "ppc, i386" stuff.
2. SDL use SDL12_compat built by https://github.com/Alexco500/libsdl12-compat.
3. LD_FLAG add "-rpath @executable_path/../Frameworks" and "-ld_classic".

Since I do not want to sign the build, a process is need after get the app: codesign --force --deep --sign - Hexen_II-gl.app

Both gl and software built for Apple Native. build-result.zip

My post on Bilibili, just see the pictures. Sorry for the language inconvenience... https://www.bilibili.com/opus/940317157468667941