feat(hwcdc): fix delay

Fixes delay when CDC is disconnected. At this time is only fixes it when USB cable is unplugged.

Author: SuGlider

Diff for: cores/esp32/HWCDC.h

@@ -46,6 +46,7 @@ class HWCDC: public Stream
 {
 private:
     static bool deinit(void * busptr);
+    static bool isCDC_Connected();
 
 public:
     HWCDC();