Nucleo-F746ZG: Use the serial console over /dev/ttyACM0 by default. The...

Nucleo-F746ZG: Use the serial console over /dev/ttyACM0 by default.  The Nucleo-F746ZG doesn't come with Arduio RS-232 shield, then it is better to use the serial over the /dev/ttyACM0 that is created automatically when the board is plugged in the computer.

configs/nucleo-144/f746-nsh/defconfig

@@ -28,6 +28,7 @@ CONFIG_NSH_BUILTIN_APPS=y
 CONFIG_NSH_FILEIOSIZE=512
 CONFIG_NSH_LINELEN=64
 CONFIG_NSH_READLINE=y
+CONFIG_NUCLEO_CONSOLE_VIRTUAL=y
 CONFIG_PREALLOC_MQ_MSGS=4
 CONFIG_PREALLOC_TIMERS=4
 CONFIG_PREALLOC_WDOGS=4
@@ -46,6 +47,6 @@ CONFIG_START_YEAR=2015
 CONFIG_STM32F7_SERIALBRK_BSDCOMPAT=y
 CONFIG_STM32F7_USART_BREAKS=y
 CONFIG_TASK_NAME_SIZE=0
-CONFIG_USART6_SERIAL_CONSOLE=y
+CONFIG_USART3_SERIAL_CONSOLE=y
 CONFIG_USER_ENTRYPOINT="nsh_main"
 CONFIG_WDOG_INTRESERVE=0