Examples: OpenGL fixed-pipeline: added glBindTexture(0), via Anton M

examples/opengl_example/imgui_impl_glfw.cpp

@@ -87,6 +87,7 @@ static void ImGui_ImplGlfw_RenderDrawLists(ImDrawList** const cmd_lists, int cmd
     glDisableClientState(GL_COLOR_ARRAY);
     glDisableClientState(GL_TEXTURE_COORD_ARRAY);
     glDisableClientState(GL_VERTEX_ARRAY);
+    glBindTexture(GL_TEXTURE_2D, 0);
     glMatrixMode(GL_MODELVIEW);
     glPopMatrix();
     glMatrixMode(GL_PROJECTION);