New unified cmake options

[halx99]

Old cmake options

• BUILD_EXTENSIONS_XXX
• CC_COMPAT_GL

New options

• AX_ENABLE_XXX for core feature:
  • AX_ENABLE_MSEDGE_WEBVIEW2: whether enable msedge webview2, default: TRUE
  • AX_ENABLE_MFMEDIA: A future feature, whether enable microsoft media foundation for windows video player support, default: TRUE
• AX_USE_XXX:
  • AX_USE_ALSOFT: whether use openal-soft for all platforms
    • Apple platform: Use openal-soft instead system deprecated: OpenAL.framework
    • Other platforms: Always use openal-soft even this option not enabled
  • AX_USE_COMPAT_GL: whether use compat gl as renderer backend, default: FALSE
  • AX_USE_LUAJIT: whether use luajit, default: FALSE, use plainlua
• AX_ENABLE_EXT_XXX for extensions
• AX_WITH_XXX: usually user don't need care it