Update internal tinyxml2 code to the latest version

Periodic update of the internal tinyxml2 code for processing
XML.  This also required some changes to the "tinyxml2" target
in libncxml/Makefile.am to modify the code to compile in the
netcdf-c environment.

include/ncconfigure.h

@@ -61,7 +61,7 @@ extern "C" {
 #endif
 
 /* WARNING: in some systems, these functions may be defined as macros, so check */
-#ifndef HAVE_STRDUP
+#if ! defined(HAVE_STRDUP) || defined(__CYGWIN__)
 #ifndef strdup
 char* strdup(const char*);
 #endif

libncxml/Makefile.am

@@ -35,7 +35,20 @@ tinyxml2::
 	rm -fr ./tinyxml2 ./license.txt
 	git clone --depth=1 ${REPO}
 	cat tinyxml2/LICENSE.txt > ./license.txt
-	cat tinyxml2/tinyxml2.h > ./tinyxml2.h
-	sed -e 's/__BORLANDC__/__APPLE__/' < tinyxml2/tinyxml2.cpp \
-	| sed -e 's/ptrdiff_t/long/g' > ./tinyxml2.cpp
+	tr -d '\r' < tinyxml2/tinyxml2.h > tinyxml2.h
+	cat tinyxml2/tinyxml2.cpp \
+	| sed -e 's/__BORLANDC__/__APPLE__/' \
+	| sed -e 's/ptrdiff_t/long/g' \
+	| sed -e '/^static[ ]*FILE[*][ ]*callfopen(/i\
+\#if 0' \
+	| sed -e '/^void[ ]*XMLDocument::DeleteNode(/i\
+\#endif /*0*/\
+' \
+	| sed -e '/^XMLError[ ]*XMLDocument::LoadFile([ ]*const[ ]*char[*]/i\
+\#if 0' \
+	| sed -e '/^XMLError[ ]*XMLDocument::Parse(/i\
+\#endif /*0*/\
+' \
+	| tr -d '\r' \
+	| cat > ./tinyxml2.cpp
 	rm -fr tinyxml2

libncxml/tinyxml2.cpp

@@ -2283,6 +2283,7 @@ XMLUnknown* XMLDocument::NewUnknown( const char* str )
     return unk;
 }
 
+#if 0
 static FILE* callfopen( const char* filepath, const char* mode )
 {
     TIXMLASSERT( filepath );
@@ -2299,6 +2300,8 @@ static FILE* callfopen( const char* filepath, const char* mode )
     return fp;
 }
 
+#endif /*0*/
+
 void XMLDocument::DeleteNode( XMLNode* node )	{
     TIXMLASSERT( node );
     TIXMLASSERT(node->_document == this );
@@ -2317,6 +2320,7 @@ void XMLDocument::DeleteNode( XMLNode* node )	{
 }
 
 
+#if 0
 XMLError XMLDocument::LoadFile( const char* filename )
 {
     if ( !filename ) {
@@ -2420,6 +2424,8 @@ XMLError XMLDocument::SaveFile( FILE* fp, bool compact )
 }
 
 
+#endif /*0*/
+
 XMLError XMLDocument::Parse( const char* xml, size_t nBytes )
 {
     Clear();