package/grpc: add GRPC_CPE_ID_VENDOR

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

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

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
(cherry picked from commit ea77594f3fb2bfab7fe0bb7417fdee0f3a6ccd9a)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/grpc/grpc.mk

@@ -8,6 +8,7 @@ GRPC_VERSION = 1.35.0
 GRPC_SITE = $(call github,grpc,grpc,v$(GRPC_VERSION))
 GRPC_LICENSE = Apache-2.0
 GRPC_LICENSE_FILES = LICENSE
+GRPC_CPE_ID_VENDOR = grpc
 
 GRPC_INSTALL_STAGING = YES