Fixes in multi line description generation

[luojia65]

This pull request contains two fixes:

1. New line separators are now rendered in enumerated values.
2. Multi line field descriptions are now rendered correctly in write and read registers.

This issue happened because the original code accidentally unescaped and respaced twice in field parse proccess. It uses escaped description L292 as input, but in desctiption_with_bits function later L1001 it unescaped again, resulting in loss of new line separators \n.

Before:

After:

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @Emilgardis (or someone else) soon.

Please see the contribution instructions for more information.

[burrbull]

LGTM. Update changelog, please.

[luojia65]

@burrbull Thanks for noting! I have updated changelog just now.

[luojia65]

The CI check failed just now for code format, I used cargo fmt and committed again. @burrbull I am sorry but would you mind approve these changes again?

[burrbull]

squash commits, pls

[luojia65]

Squashed into 1 commit

[burrbull]

bors r+

[bors]

Build succeeded:

• CI