[libxml2] Fix check for libtool in autogen.sh

[Nick Wellnhofer <nwellnhof src gnome org>]

commit ff05c94a6e45924402045b1fec602b2deb5ce3cf
Author: Nick Wellnhofer <wellnhofer aevum de>
Date:   Sun Jan 16 13:56:17 2022 +0100

    Fix check for libtool in autogen.sh
    
    libtoolize is named glibtoolize on some macOS systems.

 autogen.sh | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
---
diff --git a/autogen.sh b/autogen.sh
index d03a40c8..3778be71 100755
--- a/autogen.sh
+++ b/autogen.sh
@@ -16,7 +16,8 @@ DIE=0
        DIE=1
 }
 
-(libtoolize --version) < /dev/null > /dev/null 2>&1 || {
+(libtoolize --version) < /dev/null > /dev/null 2>&1 ||
+(glibtoolize --version) < /dev/null > /dev/null 2>&1 || {
        echo
        echo "You must have libtool installed to compile libxml."
        echo "Download the appropriate package for your distribution,"