treewide: remove aliases in nixpkgs

This makes the command ‘nix-env -qa -f. --arg config '{skipAliases =
true;}'’ work in Nixpkgs.

Misc...

- qtikz: use libsForQt5.callPackage

  This ensures we get the right poppler.

- rewrites:

  docbook5_xsl -> docbook_xsl_ns
  docbook_xml_xslt -> docbook_xsl

diffpdf: fixup

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

@@ -1,5 +1,5 @@
 { stdenv, fetchurl
-, libsysfs, gnutls, openssl
+, sysfsutils, gnutls, openssl
 , libcap, opensp, docbook_sgml_dtd_31
 , libidn, nettle
 , SGMLSpm, libgcrypt }:
@@ -26,7 +26,7 @@ stdenv.mkDerivation rec {
 
   depsBuildBuild = [ opensp SGMLSpm docbook_sgml_dtd_31 ];
   buildInputs = [
-    libsysfs openssl libcap libgcrypt nettle
+    sysfsutils openssl libcap libgcrypt nettle
   ] ++ stdenv.lib.optional (!stdenv.hostPlatform.isMusl) libidn;
 
   # ninfod probably could build on cross, but the Makefile doesn't pass --host etc to the sub configure...