Update LV_OPA_MIN and LV_OPA_MAX to widien the opacity processed range
Update LV_OPA_MIN and LV_OPA_MAX to widien the opacity processed range

https://forum.lvgl.io/t/blending-fading-of-body-shadow/2466

littlevgl/lvgl,littlevgl/lvgl,littlevgl/lvgl,littlevgl/lvgl