There is a very annoying bug at present where the terminal echos part
of the first command sent to the board. This happens because the
terminal is still set to echo for a period until Labgrid starts up and
can change this.
Fix this by disabling echo (and other terminal features) as soon as the
spawn happens.
Signed-off-by: Simon Glass <sjg@chromium.org>
5825ddccc6