Using multiple GPIO interrupts is not supported yet (e.g. 4 on P4)

[bjoernQ]

No description provided.

[bugadani]

The P4 is slightly weird in that it allows listening for a single event, but can route it to any or all of the 4 interrupt signals. We'll have to make sure we don't end up with a confusing API. I also suggest a separate, cfg-gated listen function to set up listening, so that users of the earlier/simpler MCUs don't have to deal with a single-variant enum (or EnumSet...).

[MabezDev]

We're not stabilizing interrupts for 1.0 (context: #2900 (comment)), so we can't punt this till post 1.0

[MabezDev]

@tommasoclini please file a separate issue.

[tommasoclini]

I will, should i attach the whole project with Cargo.toml and Cargo.lock, or is the code snippet fine?