Add a flag to the executable to load a configuration file

On NixOS, this is needed (apparently, experimenting right now) to load a configuration file. This is needed in thermald for example https://github.com/NixOS/nixpkgs/blob/nixos-unstable/nixos/modules/services/hardware/thermald.nix#L60

[zhang-rui]

do you mean that we should have a default mode if we didn't found a proper config file to load?

no, this
https://github.com/intel/thermal_daemon/blob/master/man%2Fthermald.8#L62

[zhang-rui]

Got it, currently I have some patches that I'd like to submit soon, and will check this after those patches submitted.

[zhang-rui]

On NixOS, this is needed (apparently, experimenting right now) to load a configuration file. This is needed in thermald for example https://github.com/NixOS/nixpkgs/blob/nixos-unstable/nixos/modules/services/hardware/thermald.nix#L60

I think you actually mean this line, right?
https://github.com/NixOS/nixpkgs/blob/nixos-unstable/nixos/modules/services/hardware/thermald.nix#L61

yes, it seems stuff changed, but indeed, it's that