Port to platforms with Xrender lib but not header

* configure.ac (HAVE_XRENDER): Also require ‘#include
<X11/extensions/Xrender.h>’ to work.  Problem found
on gcc119 in GCC compile farm.

configure.ac

@@ -3288,7 +3288,8 @@ fi
 # Check for XRender
 HAVE_XRENDER=no
 if test "${HAVE_X11}" = "yes"; then
-  AC_CHECK_LIB(Xrender, XRenderQueryExtension, HAVE_XRENDER=yes)
+  AC_CHECK_HEADER([X11/extensions/Xrender.h],
+    [AC_CHECK_LIB([Xrender], [XRenderQueryExtension], [HAVE_XRENDER=yes])])
   if test $HAVE_XRENDER = yes; then
     XRENDER_LIBS="-lXrender"
     AC_SUBST(XRENDER_LIBS)