package/leptonica: add LEPTONICA_CPE_ID_VENDOR

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

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

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

package/leptonica/leptonica.mk

@@ -8,6 +8,7 @@ LEPTONICA_VERSION = 1.80.0
 LEPTONICA_SITE = http://www.leptonica.org/source
 LEPTONICA_LICENSE = BSD-2-Clause
 LEPTONICA_LICENSE_FILES = leptonica-license.txt
+LEPTONICA_CPE_ID_VENDOR = leptonica
 LEPTONICA_INSTALL_STAGING = YES
 LEPTONICA_DEPENDENCIES = host-pkgconf