thermald: 2.2 -> 2.3
thermald: 2.2 -> 2.3

Also cleanup the derivation:
- remove unnecessary PKG_CONFIG_PATH export
- change gpl2 to gpl2Only
- add meta.changelog
- reformat inputs and sort alphabetically
last three suggested by @drewrisinger.

NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs