package/mender: add MENDER_CPE_ID_VENDOR

cpe:2.3:a:northern.tech:mender is a valid CPE identifier for this
package:

  https://nvd.nist.gov/products/cpe/detail/F90CE0C3-FCE6-40AA-8C0D-EDE2C81BD67B

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
(cherry picked from commit f4a9cdb1f85c376c18a432208ce62c7d45d7b6da)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/mender/mender.mk

@@ -7,6 +7,7 @@
 MENDER_VERSION = 3.4.0
 MENDER_SITE = $(call github,mendersoftware,mender,$(MENDER_VERSION))
 MENDER_LICENSE = Apache-2.0, BSD-2-Clause, BSD-3-Clause, ISC, MIT, OLDAP-2.8
+MENDER_CPE_ID_VENDOR = northern.tech
 
 # Vendor license paths generated with:
 #    awk '{print $2}' LIC_FILES_CHKSUM.sha256 | grep vendor