ContentServices: Handle null LocationEntry Path in VerifyContentType (#506)

When `LocationEntry.ContentPath` is `null`, we can always return `false` as it can't possibly be a valid `ContentType`

Ryujinx.HLE/FileSystem/VirtualFileSystem.cs

@@ -78,6 +78,7 @@ namespace Ryujinx.HLE.FileSystem
             {
                 return null;
             }
+
             return GetFullPath(MakeDirAndGetFullPath(Parts[0]), Parts[1]);
         }