package/perl-xml-libxml: add CPE variables

cpe:2.3:a:xml-libxml_project:xml-libxml is a valid CPE identifier for
this package:

  https://nvd.nist.gov/products/cpe/search/results?namingFormat=2.3&keyword=cpe%3A2.3%3Aa%3Axml-libxml_project%3Axml-libxml

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
(cherry picked from commit 26d9863c8248943e9bd5d3761cfd8306013fb8c6)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/perl-xml-libxml/perl-xml-libxml.mk

@@ -10,6 +10,8 @@ PERL_XML_LIBXML_SITE = $(BR2_CPAN_MIRROR)/authors/id/S/SH/SHLOMIF
 PERL_XML_LIBXML_DEPENDENCIES = zlib libxml2
 PERL_XML_LIBXML_LICENSE = Artistic or GPL-1.0+
 PERL_XML_LIBXML_LICENSE_FILES = LICENSE
+PERL_XML_LIBXML_CPE_ID_VENDOR = xml-libxml_project
+PERL_XML_LIBXML_CPE_ID_PRODUCT = xml-libxml
 PERL_XML_LIBXML_DISTNAME = XML-LibXML
 
 PERL_XML_LIBXML_CONF_OPTS = \