libxml2: upgrade to release 2.12.5

Fixes CVE-2024-25062

Change-Id: I0e98fd919328e9633a602c4872de0b06eb972cc0
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/163734
Tested-by: Jenkins
Reviewed-by: Michael Stahl <michael.stahl@allotropia.de>
diff --git a/download.lst b/download.lst
index d8d440d..e24edd7 100644
--- a/download.lst
+++ b/download.lst
@@ -424,8 +424,8 @@ XMLSEC_TARBALL := xmlsec1-1.3.3.tar.gz
# three static lines
# so that git cherry-pick
# will not run into conflicts
LIBXML_SHA256SUM := 8c8f1092340a89ff32bc44ad5c9693aff9bc8a7a3e161bb239666e5d15ac9aaa
LIBXML_VERSION_MICRO := 3
LIBXML_SHA256SUM := a972796696afd38073e0f59c283c3a2f5a560b5268b4babc391b286166526b21
LIBXML_VERSION_MICRO := 5
LIBXML_TARBALL := libxml2-2.12.$(LIBXML_VERSION_MICRO).tar.xz
# three static lines
# so that git cherry-pick