Cellular: Fix Quectel BG96 driver RTS/CTS setup

Author: Ari Parkkila

features/cellular/framework/targets/QUECTEL/BG96/QUECTEL_BG96.cpp

@@ -73,7 +73,7 @@ void QUECTEL_BG96::set_ready_cb(Callback<void()> callback)
 CellularDevice *CellularDevice::get_default_instance()
 {
     static UARTSerial serial(MBED_CONF_QUECTEL_BG96_TX, MBED_CONF_QUECTEL_BG96_RX, MBED_CONF_QUECTEL_BG96_BAUDRATE);
-#if defined (MBED_CONF_UBLOX_AT_RTS) && defined(MBED_CONF_UBLOX_AT_CTS)
+#if defined (MBED_CONF_QUECTEL_BG96_RTS) && defined(MBED_CONF_QUECTEL_BG96_CTS)
     tr_debug("QUECTEL_BG96 flow control: RTS %d CTS %d", MBED_CONF_QUECTEL_BG96_RTS, MBED_CONF_QUECTEL_BG96_CTS);
     serial.set_flow_control(SerialBase::RTSCTS, MBED_CONF_QUECTEL_BG96_RTS, MBED_CONF_QUECTEL_BG96_CTS);
 #endif

features/cellular/framework/targets/QUECTEL/BG96/QUECTEL_BG96_CellularStack.cpp

@@ -255,10 +255,6 @@ nsapi_size_or_error_t QUECTEL_BG96_CellularStack::socket_sendto_impl(CellularSoc
         return NSAPI_ERROR_PARAMETER;
     }
 
-    if (!size && socket->proto == NSAPI_UDP) {
-        return NSAPI_ERROR_UNSUPPORTED;
-    }
-
     int sent_len = 0;
     int sent_len_before = 0;
     int sent_len_after = 0;