mpy-cross: Disable stack check when building with Emscripten.
mpy-cross: Disable stack check when building with Emscripten.

`mpy-cross` can be compiled to WASM using Emscripten, but it is not happy
unless the stack check is disabled.

Signed-off-by: David Lechner <aa743a0aaec8f7d7a1f01442503957f4d7a2d634@pybricks.com>

bvernoux/micropython,adafruit/circuitpython,adafruit/circuitpython,bvernoux/micropython,adafruit/circuitpython,bvernoux/micropython,adafruit/circuitpython,bvernoux/micropython,adafruit/circuitpython,adafruit/circuitpython,bvernoux/micropython