bump esp-hal to v0.21.0

[kaspar030]

Description

Bumps esp-hal to 0.21.0 + our patches.

Issues/PRs references

Depends on #399.

Open Questions

Change checklist

• I have cleaned up my commit history and squashed fixup commits.
• I have followed the Coding Conventions.
• I have performed a self-review of my own code.
• I have made corresponding changes to the documentation.

[kaspar030]

With this, WiFi now works on the esp32-wroom-32!

[ROMemories]

esp-hal just released v0.21.0 🎉

[kaspar030]

This cargo-deny error seems like a bug:

INFO resolve: Resolving package: 'cargo-deny'
 WARN The package cargo-deny v0.16.1 (x86_64-unknown-linux-musl) has been downloaded from github.com
 INFO This will install the following binaries:
 INFO   - cargo-deny (cargo-deny -> /home/runner/.cargo/bin/cargo-deny)
 INFO Installing binaries...
 INFO Done in 1.838378756s
thread '<unnamed>' panicked at /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/krates-0.17.1/src/builder.rs:718:25:
internal error: entered unreachable code: unable to locate defmt-03 for crate registry+https://github.com/rust-lang/crates.io-index#[email protected] features(["unproven"])
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
Error: Process completed with exit code 101.

[kaspar030]

I've tested examples/embassy-http-server with the c6, plain esp32 and the s3. s3 goes into a boot loop, but also does so on main.

[ROMemories]

Successfully tested examples/gpio and examples-http-server on esp32c6.
LGTM!

[elenaf9]

Unfortunately this PR broke threading for xtensa, not sure why. Both threading examples don't work anymore on main, but still worked on the commit before this PR.