Add xml2 as skipped /contrib Makefile entry.

contrib/Makefile

-# $PostgreSQL: pgsql/contrib/Makefile,v 1.47 2003/11/29 19:51:18 pgsql Exp $
+# $PostgreSQL: pgsql/contrib/Makefile,v 1.48 2004/03/05 05:15:16 momjian Exp $
 
 subdir = contrib
 top_builddir = ..
@@ -55,6 +55,7 @@ WANTED_DIRS = \
 #		start-scripts	\ (does not have a makefile)
 #		tools		\ (does not have a makefile)
 #		xml		\ (non-standard makefile)
+#		xml2		\ (non-standard makefile)
 
 
 all install installdirs uninstall clean distclean maintainer-clean check installcheck: