add tud_mounted() check in tud_cdc_connected()

mark device as disconnected immed with DCD_EVENT_UNPLUGGED

src/class/cdc/cdc_device.c

@@ -99,7 +99,7 @@ static void _prep_out_transaction (uint8_t itf)
 bool tud_cdc_n_connected(uint8_t itf)
 {
   // DTR (bit 0) active  is considered as connected
-  return TU_BIT_TEST(_cdcd_itf[itf].line_state, 0);
+  return tud_mounted() && TU_BIT_TEST(_cdcd_itf[itf].line_state, 0);
 }
 
 uint8_t tud_cdc_n_get_line_state (uint8_t itf)

src/class/cdc/cdc_device.h

@@ -97,7 +97,6 @@ ATTR_WEAK void tud_cdc_line_coding_cb(uint8_t itf, cdc_line_coding_t const* p_li
 
 //--------------------------------------------------------------------+
 // INTERNAL USBD-CLASS DRIVER API
-
 //--------------------------------------------------------------------+
 void cdcd_init               (void);
 bool cdcd_open               (uint8_t rhport, tusb_desc_interface_t const * p_interface_desc, uint16_t *p_length);