Fixed HLSL visibility when toggling off/on

- sliders will be hidden when toggled off and will be shown when toggled
on again

src/osd/modules/render/d3d/d3dhlsl.cpp

@@ -416,6 +416,8 @@ void shaders::toggle()
 		{
 			// free shader resources before renderer resources
 			delete_resources(false);
+
+			g_slider_list = NULL;
 		}
 
 		master_enable = !master_enable;
@@ -440,6 +442,10 @@ void shaders::toggle()
 			{
 				master_enable = false;
 			}
+			else
+			{
+				g_slider_list = init_slider_list();
+			}
 		}
 	}
 }