libretro: Add compatibility settings loading

src/frontend-common/game_settings.cpp

@@ -11,10 +11,12 @@
 #include <utility>
 Log_SetChannel(GameSettings);
 
+#ifndef LIBRETRO
 #ifdef WIN32
 #include "common/windows_headers.h"
 #endif
 #include "SimpleIni.h"
+#endif
 
 namespace GameSettings {
 
@@ -173,6 +175,8 @@ bool Entry::SaveToStream(ByteStream* stream) const
          WriteStringToStream(stream, memory_card_2_shared_path) && WriteStringToStream(stream, input_profile_name);
 }
 
+#ifndef LIBRETRO
+
 static void ParseIniSection(Entry* entry, const char* section, const CSimpleIniA& ini)
 {
   for (u32 trait = 0; trait < static_cast<u32>(Trait::Count); trait++)
@@ -467,6 +471,8 @@ void Database::SetEntry(const std::string& code, const std::string& name, const
     m_entries.emplace(code, entry);
 }
 
+#endif
+
 void Entry::ApplySettings(bool display_osd_messages) const
 {
   constexpr float osd_duration = 10.0f;