feat: add k10temp cpu temperature support to fetch service

[Anomalocaridid]

Currently FetchService.cpu_temp() only works for CPUs that use the x86_pkg_temp_thermal driver, which is used by various Intel CPUs.

This adds support for CPUs that rely on the k10temp driver, namely, various AMD CPUS.

I also factored the code for checking both kinds into their own private functions that get called by cpu_temp() so the distinction is clearer and for ease of maintenance if support for other temperature drivers is added.

The practical difference as far as I am aware is pretty much just that they expose temperature information in files in different system directories, which have different structures.

I do not own any machines that use the x86_pkg_temp_thermal driver, so I cannot verify that I did not accidentally break that code, but as far as I can tell, I have not changed that part of the code other than to extract it into its own function.

[linkfrg]

Thanks!
I tested it on my Intel (x86_pkg_temp_thermal) machine and it works as usual.