package/dovecot: add DOVECOT_CPE_ID_VENDOR

cpe:2.3:a:dovecot:dovecot is a valid CPE identifier for this package:

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

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

package/dovecot/dovecot.mk

@@ -10,6 +10,7 @@ DOVECOT_SITE = https://dovecot.org/releases/$(DOVECOT_VERSION_MAJOR)
 DOVECOT_INSTALL_STAGING = YES
 DOVECOT_LICENSE = LGPL-2.1, MIT, Public Domain, BSD-3-Clause, Unicode-DFS-2015
 DOVECOT_LICENSE_FILES = COPYING COPYING.LGPL COPYING.MIT
+DOVECOT_CPE_ID_VENDOR = dovecot
 DOVECOT_DEPENDENCIES = \
 	host-pkgconf \
 	$(if $(BR2_PACKAGE_LIBICONV),libiconv) \