Use percentage instead of IsFull

Author: Riksu9000

src/components/battery/BatteryController.h

@@ -32,10 +32,6 @@ namespace Pinetime {
         return isPowerPresent;
       }
 
-      bool IsFull() const {
-        return isFull;
-      }
-
     private:
       static Battery* instance;
       nrf_saadc_value_t saadc_value;

src/displayapp/screens/BatteryInfo.cpp

@@ -63,7 +63,7 @@ void BatteryInfo::Refresh() {
   if (batteryController.IsCharging()) {
     lv_obj_set_style_local_bg_color(charging_bar, LV_BAR_PART_INDIC, LV_STATE_DEFAULT, LV_COLOR_RED);
     lv_label_set_text_static(status, "Charging");
-  } else if (batteryController.IsFull()) {
+  } else if (batteryPercent == 100) {
     lv_obj_set_style_local_bg_color(charging_bar, LV_BAR_PART_INDIC, LV_STATE_DEFAULT, LV_COLOR_BLUE);
     lv_label_set_text_static(status, "Fully charged");
   } else if (batteryPercent < 10) {