[All] Fixed multiple issues during build on Linux

- Added some fixes introduced by RodoMa92 in PR198

- Lack of AVX2 extension (should be done differently in the future)
- Disable deprecated-volatile warning
- Added missing override in posix EventInfo, ImGui notification class and XContent class
- Removed not used XAudio2.h include in XMP
- Fixed missing switch-case in XObject
- Added fugly template in native_list.h
- Fixed multiple smaller issues

src/xenia/base/console_app_main_posix.cc

@@ -23,7 +23,7 @@ extern "C" int main(int argc, char** argv) {
   }
 
   // Initialize logging. Needs parsed cvars.
-  xe::InitializeLogging(entry_info.name);
+  // xe::InitializeLogging(entry_info.name);
 
   std::vector<std::string> args;
   for (int n = 0; n < argc; n++) {
@@ -32,7 +32,7 @@ extern "C" int main(int argc, char** argv) {
 
   int result = entry_info.entry_point(args);
 
-  xe::ShutdownLogging();
+  // xe::ShutdownLogging();
 
   return result;
 }