fixed x3d importer test

test/unit/utX3DImportExport.cpp

@@ -52,7 +52,7 @@ public:
     virtual bool importerTest() {
         Assimp::Importer importer;
         const aiScene *scene = importer.ReadFile(ASSIMP_TEST_MODELS_DIR "/X3D/ComputerKeyboard.x3d", aiProcess_ValidateDataStructure);
-        return nullptr == scene;
+        return nullptr != scene;
     }
 };