stdenv: Move paxmark function to paxctl's setup hook

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

@@ -18,6 +18,8 @@ stdenv.mkDerivation rec {
     "MANDIR=share/man/man1"
   ];
 
+  setupHook = ./setup-hook.sh;
+
   meta = with stdenv.lib; {
     description = "A tool for controlling PaX flags on a per binary basis";
     homepage    = "https://pax.grsecurity.net";

pkgs/os-specific/linux/paxctl/setup-hook.sh

@@ -0,0 +1,8 @@
+# PaX-mark binaries.
+paxmark() {
+    local flags="$1"
+    shift
+
+    paxctl -c "$@"
+    paxctl -zex -${flags} "$@"
+}