Clean up some of the includes:

- explicitly include apr_lib.h since ap_config.h doesn't
- use apr_want.h where possible
- use APR_HAVE_ where possible
- remove some unneeded includes


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@88060 13f79535-47bb-0310-9956-ffa450edef68

server/util_xml.c

@@ -63,9 +63,9 @@
 #include "apr.h"
 #include "apr_strings.h"
 
-#if APR_HAVE_STDIO_H
-#include <stdio.h>              /* for fprintf(), sprintf() */
-#endif
+#define APR_WANT_STDIO          /* for fprintf(), sprintf() */
+#define APR_WANT_STRFUNC
+#include "apr_want.h"
 
 #include "httpd.h"
 #include "http_protocol.h"