Cherry pick fixes from ESP32 core upstream/master.

  millis() rollover bug
  espressif/arduino-esp32#2438

Author: everslick

Diff for: cores/esp32/esp32-hal-misc.c

@@ -82,7 +82,11 @@ unsigned long IRAM_ATTR micros()
 
 unsigned long IRAM_ATTR millis()
 {
-    return xTaskGetTickCount() * portTICK_PERIOD_MS;
+    //return xTaskGetTickCount() * portTICK_PERIOD_MS;
+
+    // https://github.com/espressif/arduino-esp32/issues/2430
+    // https://github.com/espressif/arduino-esp32/pull/2438
+    return (unsigned long) (esp_timer_get_time() / 1000ULL);
 }
 
 void delay(uint32_t ms)

Diff for: cores/esp32/main.cpp

@@ -14,15 +14,16 @@ void loopTask(void *pvParameters)
 {
     setup();
     for(;;) {
-        micros(); //update overflow
+        // https://github.com/espressif/arduino-esp32/commit/93c45af25640435f78532cc621ea159f525e502a#diff-94536ff8ccf321f988ffa45f021f7137
+        //micros(); //update overflow
         loop();
     }
 }
 
 extern "C" void app_main()
 {
     initArduino();
-    xTaskCreatePinnedToCore(loopTask, "loopTask", 8192, NULL, 1, NULL, ARDUINO_RUNNING_CORE);
+    xTaskCreatePinnedToCore(loopTask, "loopTask", 12*1024, NULL, 1, NULL, ARDUINO_RUNNING_CORE);
 }
 
 #endif