[libxml2] Disable fuzzer tests if glob.h wasn't found

[Nick Wellnhofer <nwellnhof src gnome org>]

commit 3a1c5ee7c1394ae0acf6785eb257a0ad121230af
Author: Nick Wellnhofer <wellnhofer aevum de>
Date:   Sun Sep 4 18:22:30 2022 +0200

    Disable fuzzer tests if glob.h wasn't found

 Makefile.am  | 5 ++++-
 configure.ac | 4 +++-
 2 files changed, 7 insertions(+), 2 deletions(-)
---
diff --git a/Makefile.am b/Makefile.am
index 6b79dc9a..d567c07c 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -2,10 +2,13 @@
 
 ACLOCAL_AMFLAGS = -I m4
 
-SUBDIRS = include . doc example fuzz xstc
+SUBDIRS = include . doc example xstc
 if WITH_PYTHON
 SUBDIRS += python
 endif
+if WITH_GLOB
+SUBDIRS += fuzz
+endif
 
 DIST_SUBDIRS = include . doc example fuzz python xstc
 
diff --git a/configure.ac b/configure.ac
index 1c9da738..c4ff7527 100644
--- a/configure.ac
+++ b/configure.ac
@@ -293,7 +293,9 @@ AC_CHECK_HEADERS([
     sys/socket.h netinet/in.h arpa/inet.h netdb.h
     sys/select.h poll.h
     sys/time.h sys/timeb.h
-    dl.h dlfcn.h])
+    dl.h dlfcn.h
+    glob.h])
+AM_CONDITIONAL(WITH_GLOB, test "$ac_cv_header_glob_h" = "yes")
 
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