misc: chore: Fix shader cache & CPU cache being in different folders on non-Windows

fixes #565

src/Ryujinx.Graphics.Gpu/Shader/ShaderCache.cs

@@ -118,7 +118,7 @@ namespace Ryujinx.Graphics.Gpu.Shader
         private static string GetDiskCachePath()
         {
             return GraphicsConfig.EnableShaderCache && GraphicsConfig.TitleId != null
-                ? Path.Combine(AppDataManager.GamesDirPath, GraphicsConfig.TitleId, "cache", "shader")
+                ? Path.Combine(AppDataManager.GamesDirPath, GraphicsConfig.TitleId.ToLower(), "cache", "shader")
                 : null;
         }