package/libyaml: add LIBYAML_CPE_ID_VENDOR

cpe:2.3:a:pyyaml:libyaml is a valid CPE identifier for this package:

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

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

package/libyaml/libyaml.mk

@@ -10,6 +10,7 @@ LIBYAML_SITE = http://pyyaml.org/download/libyaml
 LIBYAML_INSTALL_STAGING = YES
 LIBYAML_LICENSE = MIT
 LIBYAML_LICENSE_FILES = License
+LIBYAML_CPE_ID_VENDOR = pyyaml
 
 $(eval $(autotools-package))
 $(eval $(host-autotools-package))