e19: enableParallelBuilding of some larger components

Some parts build too long, it seems to me, so I sped them up.

pkgs/desktops/e19/efl.nix

@@ -33,6 +33,8 @@ stdenv.mkDerivation rec {
     export PKG_CONFIG_PATH="${gst_all_1.gst-plugins-base}/lib/pkgconfig/gstreamer-video-0.10.pc:$PKG_CONFIG_PATH"
   '';
 
+  enableParallelBuilding = true;
+
   setupHook = ./efl-setup-hook.sh;
 
   meta = {

pkgs/desktops/e19/elementary.nix

@@ -10,6 +10,7 @@ stdenv.mkDerivation rec {
   preConfigure = ''
     export NIX_CFLAGS_COMPILE="-I${e19.efl}/include/ethumb-1 $NIX_CFLAGS_COMPILE"
   '';
+  enableParallelBuilding = true;
   meta = {
     description = "Widget set/toolkit";
     homepage = http://enlightenment.org/;

pkgs/desktops/e19/enlightenment.nix

@@ -19,6 +19,8 @@ stdenv.mkDerivation rec {
       --replace "/usr/share/X11/xkb/rules/xorg.lst" "${xkeyboard_config}/share/X11/xkb/rules/base.lst"
   '';
 
+  enableParallelBuilding = true;
+
   # this is a hack and without this cpufreq module is not working:
   #   when set_freqset_setuid is true and "e19_freqset" is set in setuidPrograms (this is taken care of in e19 NixOS module),
   #   then this postInstall does the folowing: