package/rpm: add RPM_CPE_ID_VENDOR

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

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

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/rpm/rpm.mk

@@ -19,6 +19,7 @@ RPM_DEPENDENCIES = \
 	$(TARGET_NLS_DEPENDENCIES)
 RPM_LICENSE = GPL-2.0 or LGPL-2.0 (library only)
 RPM_LICENSE_FILES = COPYING
+RPM_CPE_ID_VENDOR = rpm
 # We're patching configure.ac
 RPM_AUTORECONF = YES