gpio: add sloppy logic analyzer using polling

This is a sloppy logic analyzer using GPIOs. It comes with a script to
isolate a CPU for polling. While this is definitely not a production
level analyzer, it can be a helpful first view when remote debugging.
Read the documentation for details.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20240620094159.6785-2-wsa+renesas@sang-engineering.com


[Bartosz: moved the Kconfig entry into a different category]
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>