[gxml] Removed Mallard documentation

[Daniel Espinosa Ortiz <despinosa src gnome org>]

commit 9aa8d0494798e4801a7497d7f8ebe9f5f46040ca
Author: Daniel Espinosa <esodan gmail com>
Date:   Mon Nov 7 23:34:09 2016 -0600

    Removed Mallard documentation

 configure.ac |    3 ---
 1 files changed, 0 insertions(+), 3 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index c4cdf10..4d1deda 100644
--- a/configure.ac
+++ b/configure.ac
@@ -252,8 +252,6 @@ docs/valadoc/Makefile
 docs/valadoc/devhelp/Makefile
 docs/valadoc/gtk-doc/Makefile
 docs/valadoc/gir-docs/Makefile
-docs/mallard/Makefile
-docs/mallard/C/Makefile
 examples/Makefile
 examples/c/Makefile
 examples/js/Makefile
@@ -280,7 +278,6 @@ echo "   GObject Introspection:   $found_introspection"
 echo "   Documentation:           ${enable_docs}"
 echo "       DevHelp Docs:        ${build_devhelp}"
 echo "       Gtk-Docs:            ${build_gtkdoc}"
-echo "       Mallard Docs:        ${build_mallard_doc}"
 echo "   Enable Performance Test: $performance"
 echo "   Debug:                   $debug"
 echo "   Platform:                $host"