Support CONFIG_DYNAMIC_DEBUG in `_debug` logging functions

[wedsonaf]

Current pr_debug doesn't support it yet, it's either on or off depending on debug_assertions.

[ojeda]

I have #122 keeping track of different printing-related features, let me update that one.

[ojeda]

Done -- I will keep this open, since that way people can automatically close it individually from a PR.

[mrwigglewaffles]

I have started working on this. I have a working wip here.

The main problem is that the c version uses the __func__ macro to log the function name. Rust has no equivalent macro. It looks like there were a couple of proposals to add something like this to rust but they got dropped. 1, 2. I did try the trick of using core::any::type_name::<T>() to get the function name but it does not work in a const context.

Even without that, I probably will send it to the mailing list sometime soon.

zulip thread