Add fan control wrappers

[codifryed]

This adds wrappers for:

nvmlDeviceSetDefaultFanSpeed_v2
nvmlDeviceSetFanSpeed_v2

Tested working on multiple systems.

Resolves #59

[brayniac]

@codifryed - I mistakenly approved and merged this without realizing this introduced some build failures. Sorry about that. If this is still relevant, can I get you to rebase the changes on main and submit a new PR?

[raum-dellamorte]

The build failure appears to be that this created a duplicate of this commit adding fan control, #77. The functions set_fan_speed and set_default_fan_speed are identical in both this PR and #77. Close as duplicate?

I used this PR in my personal project. Yay! I can update nvfanservice to use the official crate! Or at least the official repo.

[codifryed]

Indeed, #77 (a later semi-duplicate) adds these methods plus one more to set the fan policy. I'd say #77 is preferred because of that and the unwrapped_functions update, with one exception: my branch added tests for these methods. Since these methods modify the device, they are not run by default so I don't know if they're actually wanted or not. (seems superfluous)

@brayniac I'm happy to add those test "stubs" in a new PR if you think it's a good idea, otherwise we can consider these changes already merged.

Thank you for getting around to these PRs. Now that I know it's possible, I will make more. :)

Edit: &mut self is another difference I now see. I assume mut is desired for methods that change device settings. That was something I wasn't 100% sure about originally.

[brayniac]

@codifryed - I agree the tests may be of limited use given that they are not run. While I'd happily take a PR that adds them for completeness, I'm not sure if they really serve much benefit. I think we can consider this closed by #77

I'm trying to catch up on outstanding PRs and will publish a release soon. Thanks again!

[ilya-zlobintsev]

I'm sorry - I completely forgot to check existing PRs before making #77 🤦