ldmud: 3.6.7 -> 3.6.8

Notably this update allows dropping the libxm2 compat patch since the
fix has landed upstream.

See https://groups.google.com/g/ldmud-talk/c/yCvuj6WWEBk/m/40BonmTqCwAJ
for more information.

pkgs/by-name/ld/ldmud/libxml2-2.12.0-compat.patch

@@ -1,18 +0,0 @@
-diff --git src/pkg-xml2.c src/pkg-xml2.c
-index 048ca38c..9ea4de35 100644
---- src/pkg-xml2.c
-+++ src/pkg-xml2.c
-@@ -507,8 +507,13 @@ f_xml_generate (svalue_t *sp)
-     return sp;
- }
- 
-+#if LIBXML_VERSION >= 21200
-+static void
-+xml_pkg_error_handler(void * userData, const xmlError *error)
-+#else
- static void
- xml_pkg_error_handler(void * userData, xmlErrorPtr error)
-+#endif
- {
-     if (error)
-     {

pkgs/by-name/ld/ldmud/package.nix

@@ -28,17 +28,16 @@
 
 stdenv.mkDerivation (finalAttrs: {
   pname = "ldmud";
-  version = "3.6.7";
+  version = "3.6.8";
 
   src = fetchFromGitHub {
     owner = "ldmud";
     repo = "ldmud";
     tag = finalAttrs.version;
-    hash = "sha256-PkrjP7tSZMaj61Hsn++7+CumhqFPLbf0+eAI6afP9HA=";
+    hash = "sha256-ojOLM1vkuwuF0vXx6lCH0+OlyLkkOOnTJEUiZPpUhzo=";
   };
 
   patches = [
-    ./libxml2-2.12.0-compat.patch
     ./mysql-compat.patch
   ];