Couple of fixes for the latest STM32 additions / modifications. These are simple fixes dealing with conditional compile based on CONFIG items not being set. From Ken Pettit

arch/arm/src/stm32/stm32_lowputc.c

@@ -572,9 +572,11 @@ void stm32_lowsetup(void)
   uint32_t cr;
 #endif
 
+#if defined(CONFIG_HAVE_CONSOLE)
   /* Enable USART APB1/2 clock */
 
   modifyreg32(STM32_CONSOLE_APBREG, 0, STM32_CONSOLE_APBEN);
+#endif
 
   /* Enable the console USART and configure GPIO pins needed for rx/tx.
    *

arch/arm/src/stm32/stm32_serial.c

@@ -390,8 +390,6 @@ static const struct uart_ops_s g_uart_ops =
   .rxavailable    = up_rxavailable,
 #ifdef CONFIG_SERIAL_IFLOWCONTROL
   .rxflowcontrol  = up_rxflowcontrol,
-#else
-  .rxflowcontrol  = NULL,
 #endif
   .send           = up_send,
   .txint          = up_txint,