fptl: fixed directional shadows in scene view

Assets/ScriptableRenderLoop/fptl/FptlLighting.cs

 
 				m_ShadowPass.UpdateCullingParameters(ref cullingParams);
 
-				if (CullResults.Cull(camera, renderLoop, out cullResults))
-					ExecuteRenderLoop(camera, cullResults, renderLoop);
+				cullResults = CullResults.Cull(ref cullingParams, renderLoop);
+				ExecuteRenderLoop(camera, cullResults, renderLoop);
 			}
 		}