Implement mov [DESTINATION], !x

[qbalsdon]

I would like to request the implementation of

mov [DESTINATION], !x

I would offer to do this myself but I actually have a) no idea what !x means (at least in this context) and b) don't know how to add to this repo (domain knowledge of the code)

[tannewt]

Looks like it should work if you put a space inbetween ! x. The move parsing code is here: https://github.com/adafruit/Adafruit_CircuitPython_PIOASM/blob/main/adafruit_pioasm.py#L141-L147

To support !x you'd need to test to see if the source starts with !, ~ or :: and split accordingly.

[kevinjwalters]

FYI from https://learn.adafruit.com/intro-to-rp2040-pio-with-circuitpython#faq-3084251 under mov operator restrictions says:

The official dialect allows "!" to mean the same as "~". This is not accepted by adafruit_pioasm.

[gamblor21]

Fixed in #17 if it still causes issues please let me know.