elm: call eina_value_flush to deallocate memory

I am not sure if Eina_Value allocates dynamic memory
for basic types but its better practice to call eina_value_flush()
at the end.

src/lib/elementary/efl_ui_multibuttonentry.c

@@ -278,6 +278,8 @@ _shrink_mode_set(Evas_Object *obj,
              efl_event_callback_legacy_call
                (obj, EFL_UI_MULTIBUTTONENTRY_EVENT_EXPAND_STATE_CHANGED, (void *)1);
           }
+
+        eina_value_flush(&val);
      }
    else
      {

src/lib/elementary/efl_ui_progressbar.c

@@ -118,6 +118,8 @@ _units_set(Evas_Object *obj)
         eina_strbuf_reset(sd->format_strbuf);
         sd->format_cb(sd->format_cb_data, sd->format_strbuf, val);
         elm_layout_text_set(obj, "elm.text.status", eina_strbuf_string_get(sd->format_strbuf));
+
+        eina_value_flush(&val);
      }
    else
      elm_layout_text_set(obj, "elm.text.status", NULL);

src/lib/elementary/efl_ui_slider.c

@@ -241,6 +241,8 @@ _units_set(Evas_Object *obj)
              elm_layout_signal_emit(obj, "elm,state,units,visible", "elm");
              sd->units_show = EINA_TRUE;
           }
+
+        eina_value_flush(&val);
      }
    else
      {