This replaces PR #34122, by moving it to the staging branch as requested due to the number of rebuilds it causes.

Motivation for this change

This rev-bump of libinput resolves issues with out of order key press
delivery as described here:

https://lists.freedesktop.org/archives/wayland-devel/2017-December/036147.html

Things done

In addition to the items below, I've been running this change in an overlay of unstable on two NixOS computers for several weeks without any problems.

• [*] 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.