This tool is used to compute size differences in the firmware (eg as part
of CI), but it doesn't currently check any firmware that has bare-metal
lwIP/networking, making it hard to see how firmware size changes when
networking related changes are made.
So, change the board selection for the rp2 port to RPI_PICO_W. Changes in
size to standard RPI_PICO firmware will be very similar to other bare-metal
boards like PYBV10.
Signed-off-by: Damien George <damien@micropython.org>