Add clear of MCU status registers at initialization.

bacnet-stack/ports/bdk-atxx4-mstp/dlmstp.c

@@ -1208,6 +1208,7 @@ uint16_t dlmstp_receive(
         MSTP_Flag.ReceivedValidFrameNotForUs = false;
     }
     if (Receive_State == MSTP_RECEIVE_STATE_IDLE) {
+        /* only do master state machine while rx is idle */
         while (MSTP_Master_Node_FSM()) {
             /* do nothing while some states fast transition */
         };