Re-generate register mappings with svd2rust 0.30.2

[Ironedde]

Why do we want to do this?

In the past we have introduced build and/or clippy fixes ourselfs
through individual patches. Some of these include:

fa62200 Fix clippy::unnecessary_cast, added in svd2rust 0.27.0)
e50754a Fix clippy::explicit_auto_deref, added in svd2rust 0.27.0)
c4a8906 Added Eq implementation, added in svd2rust 0.26.0

But since all these have been added up until svd2rust 0.30.2, and beacuse clippy::missing_safety_doc has started causing our PR's to fail CI, it makes sense to step up the mappings and make use of the new changes.

What is changing?

Since we are stepping the version of the generating tool of the register mappings themselfs, we can expect there to be some breaking changes here.
One example is in mcan::reg::psr::LEC_A which changes name to LECSELECT_A.

The API for the main functionality of the mcan crate will be left unchanged and hopefully this will mean that most users don't need to spend much time to update their codebase.

How do we accomplish this?

Since we have modified some structures in the generated code to fit with our use case there are some manual additions we need to make after we use svd2rust and form.

So the full process becomes:

1. Create a SVD export using svd2rust 0.30.2 and form 0.10.0
2. Copy generic.rs to mcan/src/reg/
3. Copy generic/ to mcan/src/reg/
4. Overwrite rxf{a,c,s}.rs with rxf0{a,c,s}.rs
5. Re-apply the merge the two FIFO queues (57d1266)
6. Re-apply fix for docs relating to the move into reg module, along
   with wrong docs for tdcr (2dcd7a3)
7. Re-apply the item-level docs for generics.rs
8. Remove customer specific register information from cust.rs
9. Fix build errors that was caused by the svd2rust update

Note: This update is based on the SVD file used by the atsame51n pac
crate (0.13.0).
There are newer files available, but these does not contain changes that concerns the MCAN peripheral.

Thank you!

Thank you for your contribution.
Please make sure that your submission includes the following:

Must

• The code compiles without errors or warnings.
• All tests pass and in the best case you also added new tests.
• cargo +stable fmt was run.
• cargo +stable clippy yields no warnings.
• Your changes were added to the CHANGELOG.md in the proper section.
• You add a description of your work to this PR.
• You added proper docs (in code, rustdoc and README.md) for your
  newly added features and code.

[epontan]

Looks great, @Ironedde! Well done 👍

[vcrn]

Looks good, well done!