Add missing DeriveFrom entry for address_block

[emesare]

Fixes #288

I didn't look much into it, but i'm pretty sure we only copy the address blocks if the entry is absent in the derived info.

[burrbull]

Format code and update https://github.com/rust-embedded/svd/blob/master/svd-rs/Cargo.toml please.

[emesare]

Apologies for forgetting to format! Pushed formatted commit.

What would you like me to do in the Cargo.toml?

I went and looked around for a contributing doc and a Quick Look ™️ around I could not find a reference for what to update, my guess is either incrementing the version or adding an author entry, but I will await your response before I start committing nonsense 😆

Thanks for the quick response 😄

[burrbull]

Wrong link. I meant changelog https://github.com/rust-embedded/svd/blob/master/svd-rs/CHANGELOG.md

[emesare]

Done! :)