Running
USEMODULE=stdio_rtt make BOARD=weact-g030f6 -C ... flash term
failed due the programmer not being specified by the time the serial
is configured:
makefiles/tools/serial.inc.mk:44: "Warning: No RIOT_TERMINAL set,
but using stdio_rtt: The default terminal is likely not to work."
This reorders the setup of the board to first configure the programmer
and then the serial, so that using stdio_rtt now works out of the box.