Revert "asciidoc: properly differentiate the "-full" variant in meta.description"

I changed my mind about this, I no longer think that meta.description
should differ depending on the package configuration. A package
configuration can be very fine grained, and I don't think it's
possible/preferable to describe this in meta.description.

This reverts commit 9033821c34d5cd69d814d73413da7a2e5f719d3f.

pkgs/tools/typesetting/asciidoc/default.nix

···
   preInstall = "mkdir -p $out/etc/vim";
 
   meta = with stdenv.lib; {
-    description = "Text-based document generation system ${stdenv.lib.optionalString enableStandardFeatures "(full version)"}";
+    description = "Text-based document generation system";
     longDescription = ''
       AsciiDoc is a text document format for writing notes, documentation,
       articles, books, ebooks, slideshows, web pages, man pages and blogs.