treewide: Get rid of most parseDrvName without breaking compat

That is because this commit should be merged to both master and
release-19.09.

maintainers/scripts/update.nix

@@ -126,7 +126,7 @@ let
 
   packageData = package: {
     name = package.name;
-    pname = (builtins.parseDrvName package.name).name;
+    pname = lib.getName package;
     updateScript = map builtins.toString (pkgs.lib.toList package.updateScript);
   };