Motivation for this change

Required dependency for some camera relying of the uvcdynctrl's dev utility to add and manage dynamic control (expressed as xml files) to the uvcvideo driver.

Is one actual dependency for an upcoming tiscamera package (for driving cameras from The Imaging Source).

Once / if accepted, should also base some nixos module on the contained uvcdynctrl utility to combine the *.xml data from multiple camera package to be loaded by uvcdynctrl udev rule.

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option build-use-sandbox in nix.conf on non-NixOS)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nox --run "nox-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Fits CONTRIBUTING.md.