These boards do not build with IDF v4.4 because the section .iram0.text
does not fit in region iram0_0_seg. Enabling SPIRAM increases the code
size so use -Os instead of -O2 to build these boards.
Fixes issue #8260.
This will be used by https://micropython.org/download/ to generate the
full listing of boards and firmware files.
Optionally supports a board.md for additional customisation of the
download page, as well as deploy.md for flashing instructions.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>