get rid of redundant blendmode routines

get rid of redundant blendmode routines and don't use overlay mode by
default

Assets/ScriptableRenderLoop/fptl/FptlLighting.cs

         void OnDisable()
         {
            // RenderLoop.renderLoopDelegate -= ExecuteRenderLoop;
-            DestroyImmediate(m_DeferredMaterial);
-            DestroyImmediate(m_DeferredReflectionMaterial);
+            if(m_DeferredMaterial) DestroyImmediate(m_DeferredMaterial);
+            if(m_DeferredReflectionMaterial) DestroyImmediate(m_DeferredReflectionMaterial);
             m_cookieTexArray.Release();
             m_cubeCookieTexArray.Release();
             m_cubeReflTexArray.Release();
                     //Assert(false);
                 }
 
-                ++i;
+                // next light
+                if (cl.lightType == LightType.Spot || cl.lightType == LightType.Point)
+                    ++i;
             }
 
 
             // do anything we need to do upon a new frame.
             NewFrame();
 
-            m_DeferredMaterial.SetInt("_SrcBlend", camera.hdr ? (int)BlendMode.One : (int)BlendMode.DstColor);
-            m_DeferredMaterial.SetInt("_DstBlend", camera.hdr ? (int)BlendMode.One : (int)BlendMode.Zero);
-            m_DeferredReflectionMaterial.SetInt("_SrcBlend", camera.hdr ? (int)BlendMode.One : (int)BlendMode.DstColor);
-            m_DeferredReflectionMaterial.SetInt("_DstBlend", camera.hdr ? (int)BlendMode.One : (int)BlendMode.Zero);
+            //m_DeferredMaterial.SetInt("_SrcBlend", camera.hdr ? (int)BlendMode.One : (int)BlendMode.DstColor);
+            //m_DeferredMaterial.SetInt("_DstBlend", camera.hdr ? (int)BlendMode.One : (int)BlendMode.Zero);
+            //m_DeferredReflectionMaterial.SetInt("_SrcBlend", camera.hdr ? (int)BlendMode.One : (int)BlendMode.DstColor);
+            //m_DeferredReflectionMaterial.SetInt("_DstBlend", camera.hdr ? (int)BlendMode.One : (int)BlendMode.Zero);
             loop.SetupCameraProperties(camera);
             RenderGBuffer(cullResults, camera, loop);
 

Assets/ScriptableRenderLoop/fptl/Internal-DeferredShading.shader

 
 	
 	float3 c = ExecuteLightList(pixCoord, offs);
-	c = OverlayHeatMap(FetchLightCount(offs), c);
+	//c = OverlayHeatMap(FetchLightCount(offs), c);
-	//return float4(c,1.0);
-	return float4(pow(c,1/2.2),1.0);
+	return float4(c,1.0);
+	//return float4(pow(c,1/2.2),1.0);
 }
 
 struct UnityStandardData