Get rid of all with { inherit... } and just used let inherit...

The old forms presumably predates, or were made in ignorance of,
`let inherit`. This way is better style as the scoping as more lexical,
something which Nix can (or might already!) take advantage of.

pkgs/development/libraries/cairo/default.nix

@@ -9,7 +9,7 @@
 
 assert glSupport -> mesa_noglu != null;
 
-with { inherit (stdenv.lib) optional optionals; };
+let inherit (stdenv.lib) optional optionals; in
 
 stdenv.mkDerivation rec {
   name = "cairo-1.14.8";