Use correct mask for CTS flow control

Author: Hasnain Virk

hal/targets/hal/TARGET_Freescale/TARGET_KSDK2_MCUS/TARGET_K64F/serial_api.c

@@ -288,24 +288,24 @@ void serial_set_flow_control(serial_t *obj, FlowControl type, PinName rxflow, Pi
     switch(type) {
         case FlowControlRTS:
             pinmap_pinout(rxflow, PinMap_UART_RTS);
-            uart_addrs[obj->index]->MODEM &= ~UART_MODEM_TXRTSE_MASK;
+            uart_addrs[obj->index]->MODEM &= ~UART_MODEM_TXCTSE_MASK;
             uart_addrs[obj->index]->MODEM |= UART_MODEM_RXRTSE_MASK;
             break;
 
         case FlowControlCTS:
             pinmap_pinout(txflow, PinMap_UART_CTS);
             uart_addrs[obj->index]->MODEM &= ~UART_MODEM_RXRTSE_MASK;
-            uart_addrs[obj->index]->MODEM |= UART_MODEM_TXRTSE_MASK;
+            uart_addrs[obj->index]->MODEM |= UART_MODEM_TXCTSE_MASK;
             break;
 
         case FlowControlRTSCTS:
             pinmap_pinout(rxflow, PinMap_UART_RTS);
             pinmap_pinout(txflow, PinMap_UART_CTS);
-            uart_addrs[obj->index]->MODEM |= UART_MODEM_TXRTSE_MASK | UART_MODEM_RXRTSE_MASK;
+            uart_addrs[obj->index]->MODEM |= UART_MODEM_TXCTSE_MASK | UART_MODEM_RXRTSE_MASK;
             break;
 
         case FlowControlNone:
-            uart_addrs[obj->index]->MODEM &= ~(UART_MODEM_TXRTSE_MASK | UART_MODEM_RXRTSE_MASK);
+            uart_addrs[obj->index]->MODEM &= ~(UART_MODEM_TXCTSE_MASK | UART_MODEM_RXRTSE_MASK);
             break;
 
         default: