Add Flex/AnyFlex pin drivers

[bjoernQ]

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Pull Request Details 📖

Description

This adds a Flex/AnyFlex pin driver to fix #740

Testing

The GPIO HIL-test exercises the new driver. Doesn't seem to deserve a dedicated example

[MabezDev]

This is excellent, thanks for working on this! Very nice PR.

LGTM!

[jessebraham]

I think we need much more documentation in this module. Looking at the docs with this branch included:

I can't even imagine trying to figure out which pin type I need as a user who is not familiar with the HAL. I don't even really know what half of these types do, honestly.

[bjoernQ]

I can't even imagine trying to figure out which pin type I need as a user who is not familiar with the HAL. I don't even really know what half of these types do, honestly.

I have a few ideas for improving the docs here and also on the "landing page" to help new users to have a smooth(er) start. But well - not in this PR (and we should generally wait for the doc-test PR to land before shuffling around docs I guess)

But it's definitely already much easier than the into_XXX API we had before

[bjoernQ]

I think the docs topic touches #742

[MabezDev]

I opened #1660 to track the module level doc improvements

[JurajSadel]

LGTM, thanks!