usbguard: install shell completion

pkgs/os-specific/linux/usbguard/default.nix

@@ -2,6 +2,7 @@
 , lib
 , fetchFromGitHub
 , autoreconfHook
+, installShellFiles
 , asciidoc
 , pkg-config
 , libxslt
@@ -35,6 +36,7 @@ stdenv.mkDerivation rec {
 
   nativeBuildInputs = [
     autoreconfHook
+    installShellFiles
     asciidoc
     pkg-config
     libxslt # xsltproc
@@ -66,6 +68,11 @@ stdenv.mkDerivation rec {
 
   enableParallelBuilding = true;
 
+  postInstall = ''
+    installShellCompletion --bash --name usbguard.bash scripts/bash_completion/usbguard
+    installShellCompletion --zsh --name _usbguard scripts/usbguard-zsh-completion
+  '';
+
   meta = with lib; {
     description = "The USBGuard software framework helps to protect your computer against BadUSB";
     longDescription = ''