DolphinWX: Don't use a special color for compressed games

- There's no clear definition of what it means for a GC/Wii game
  to be compressed. GC games in GCZ are obviously compressed,
  but what about formats like WBFS and CISO that just discard data?
- Hardcoded colors might have bad contrast with the used theme.
- It feels Windows XP to me.

Source/Core/Core/ConfigManager.h

@@ -289,9 +289,6 @@ struct SConfig : NonCopyable
   bool m_showSizeColumn;
   bool m_showStateColumn;
 
-  // Toggles whether compressed titles show up in blue in the game list
-  bool m_ColorCompressed;
-
   std::string m_WirelessMac;
   bool m_PauseMovie;
   bool m_ShowLag;