Upgrade to libxml 2.9.2 and libxslt 1.1.28

third_party/libxml/src/include/libxml/Makefile.am

Index: third_party/libxml/src/include/libxml/Makefile.am
diff --git a/third_party/libxml/src/include/libxml/Makefile.am b/third_party/libxml/src/include/libxml/Makefile.am
new file mode 100644
index 0000000000000000000000000000000000000000..cf9297aad66b00d498cab89883985c552ae2febb
--- /dev/null
+++ b/third_party/libxml/src/include/libxml/Makefile.am
@@ -0,0 +1,54 @@
+## Process this file with automake to produce Makefile.in
+
+xmlincdir = $(includedir)/libxml2/libxml
+
+xmlinc_HEADERS = \
+		SAX.h \
+		entities.h \
+		encoding.h \
+		parser.h \
+		parserInternals.h \
+		xmlerror.h \
+		HTMLparser.h \
+		HTMLtree.h \
+		debugXML.h \
+		tree.h \
+		list.h \
+		hash.h \
+		xpath.h \
+		xpathInternals.h \
+		xpointer.h \
+		xinclude.h \
+		xmlIO.h \
+		xmlmemory.h \
+		nanohttp.h \
+		nanoftp.h \
+		uri.h \
+		valid.h \
+		xlink.h \
+		xmlversion.h \
+		DOCBparser.h \
+		catalog.h \
+		threads.h \
+		globals.h \
+		c14n.h \
+		xmlautomata.h \
+		xmlregexp.h \
+		xmlmodule.h \
+		xmlschemas.h \
+		schemasInternals.h \
+		xmlschemastypes.h \
+		xmlstring.h \
+		xmlunicode.h \
+		xmlreader.h \
+		relaxng.h \
+		dict.h \
+		SAX2.h \
+		xmlexports.h \
+		xmlwriter.h \
+		chvalid.h \
+		pattern.h \
+		xmlsave.h \
+		schematron.h
+
+EXTRA_DIST = xmlversion.h.in