package/nginx: add NGINX_CPE_ID_VENDOR

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

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

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/nginx/nginx.mk

@@ -8,6 +8,7 @@ NGINX_VERSION = 1.18.0
 NGINX_SITE = http://nginx.org/download
 NGINX_LICENSE = BSD-2-Clause
 NGINX_LICENSE_FILES = LICENSE
+NGINX_CPE_ID_VENDOR = nginx
 NGINX_DEPENDENCIES = host-pkgconf
 
 NGINX_CONF_OPTS = \