langtag: worked around reg2xml libxml2 encoding problem

libxml2 has a problem when a document encoding is specified, even though
documentation says that all internal representation would be in UTF-8 and
language-subtag-registry data already is passed in UTF-8, when specifying the
document encoding to be UTF-8 the output to language-subtag-registry.xml is
conversion garbage, '?' on Linux UTF-8 locale, ISO-8859-1 on Windows. If no
document encoding is specified at all no conversion happens and non-ASCII
values are correctly written as entities.

liblangtag/liblangtag-0.2-reg2xml-encoding-problem.patch

+# libxml2 has a problem when a document encoding is specified, even though
+# documentation says that all internal representation would be in UTF-8 and
+# language-subtag-registry data already is passed in UTF-8, when specifying the
+# document encoding to be UTF-8 the output to language-subtag-registry.xml is
+# conversion garbage, '?' on Linux UTF-8 locale, ISO-8859-1 on Windows. If no
+# document encoding is specified at all no conversion happens and non-ASCII
+# values are correctly written as entities.
+
+--- misc/liblangtag-0.2/data/reg2xml.c	2012-01-30 13:20:57.000000000 +0100
++++ misc/build/liblangtag-0.2/data/reg2xml.c	2012-08-11 02:30:39.147779753 +0200
+@@ -144,7 +144,6 @@
+ 	gboolean retval;
+ 
+ 	doc = xmlNewDoc((const xmlChar *)"1.0");
+-	doc->encoding = xmlStrdup((const xmlChar *)"UTF-8");
+ 	root = xmlNewDocNode(doc, NULL,
+ 			     (const xmlChar *)"registry",
+ 			     NULL);

liblangtag/makefile.mk

@@ -41,6 +41,7 @@ PATCH_FILES+=liblangtag-0.2-0002-Fix-invalid-memory-access.patch
 PATCH_FILES+=liblangtag-0.2-configure.patch
 PATCH_FILES+=liblangtag-0.2-datadir.patch
 PATCH_FILES+=liblangtag-0.2-msvc-warning.patch
+PATCH_FILES+=liblangtag-0.2-reg2xml-encoding-problem.patch
 
 CONFIGURE_DIR=.
 BUILD_DIR=$(CONFIGURE_DIR)