Remove most trait implementation features from esp-hal

[jessebraham]

This began as a quest to eliminate the async feature, however we came to the conclusion that none of these features are really necessary, and they just needlessly complicate things. These packages largely contain a couple traits and/or types only, so build times should not be affected significantly.

If anybody thinks any of these features should remain I'm willing to hear your arguments, but as I said I really don't think there is any need.

Closes #2007

[jessebraham]

The changes to esp-wifi do not warrant a CHANGELOG.md entry IMO, so I have added skip-changelog; I have still recorded the changes for esp-hal.

[bugadani]

I think embassy-usb* should still be gated, behind usb-otg.

[Dominaezzz]

I'm glad async going away as it was annoying to deal with within the hal, but the dependency based features on the other hand I'm not so sure.

I have two arguments:

1. This conversation, sometimes the overloads from these traits can get in your way. I can also imagine conflicts between e-hal v1 and v0.2 .
2. It doesn't happen often but some dependencies can have issues building and it's nice to be able to not include it. Particularly pre-1.0 libraries. I'd rather not have my hands tied by esp-hal hard including a problematic (to me) version of a package.

[bugadani]

My suggestion is to roll with this and deal with the fallout later, if there is any. embassy is usually a pretty good example to follow and they don't have any issues with similarly unconditional implementations.

[JurajSadel]

Thanks!

[bjoernQ]

Reminder to not merge before we released #2004 is released

[jessebraham]

Welp just nuked this branch by accident, oops. Will fix at some point and either re-open this or open a new PR.