Fix Usage of Bootsel Button for Pico 2

[subsonicpulse]

Function board_button_read() was always returning TRUE on pico 2 board.

This fix make the button on pico2 board usable again.
The code that fixes the problem is from https://github.com/raspberrypi/pico-examples/blob/master/picoboard/button/button.c

[subsonicpulse]

I tested that on pico and pico 2 with the HID example:
pico-sdk\sdk\2.0.0\lib\tinyusb\examples\device\hid_multiple_interface\src

[hathach]

thank you for the fix, tested and working great. I change the ifdef condition to detect arm arch to make it more generic for other vendor pico/pico2 board.

[subsonicpulse]

thank you for the fix, tested and working great. I change the ifdef condition to detect arm arch to make it more generic for other vendor pico/pico2 board.

Thanks also. I was not aware of these Preprocessor Macros. I just used what was in the pico example code. ;-)

[subsonicpulse]

Thank you.
Really nice. I was not aware of the ARM preprocessor define.
Thats of course a more generic solution.