Treewide: use HTTPS on GNU domains

HTTP -> HTTPS for :
- http://gnu.org/
- http://www.gnu.org/
- http://elpa.gnu.org/
- http://lists.gnu.org/
- http://gcc.gnu.org/
- http://ftp.gnu.org/ (except in fetchurl mirrors)
- http://bugs.gnu.org/

pkgs/development/libraries/libopcodes/default.nix

@@ -36,7 +36,7 @@ stdenv.mkDerivation rec {
 
   meta = with stdenv.lib; {
     description = "A library from binutils for manipulating machine code";
-    homepage = http://www.gnu.org/software/binutils/;
+    homepage = https://www.gnu.org/software/binutils/;
     license = licenses.gpl3Plus;
     maintainers = with maintainers; [ ericson2314 ];
     platforms = platforms.unix;