fix(demo): fix showing the average FPS

demos/music/lv_demo_music.c

@@ -12,6 +12,7 @@
 
 #include "lv_demo_music_main.h"
 #include "lv_demo_music_list.h"
+#include "../../src/core/lv_global.h"
 
 /*********************
  *      DEFINES
@@ -103,6 +104,10 @@ static const uint32_t time_list[] = {
     2 * 60 + 19,
 };
 
+#if LV_USE_PERF_MONITOR || LV_DEMO_MUSIC_AUTO_PLAY
+    #define sysmon_perf LV_GLOBAL_DEFAULT()->sysmon_perf
+#endif
+
 /**********************
  *      MACROS
  **********************/
@@ -225,7 +230,8 @@ static void auto_step_cb(lv_timer_t * t)
                 lv_obj_t * num = lv_label_create(bg);
                 lv_obj_set_style_text_font(num, font_large, 0);
 #if LV_USE_PERF_MONITOR
-                lv_label_set_text_fmt(num, "%" LV_PRIu32, lv_refr_get_fps_avg());
+                const lv_sysmon_perf_info_t * info = lv_subject_get_pointer(&sysmon_perf.subject);
+                lv_label_set_text_fmt(num, "%" LV_PRIu32, info->calculated.cpu_avg_total);
 #endif
                 lv_obj_align(num, LV_ALIGN_TOP_MID, 0, 120);