vtun: add license info

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/vtun/vtun.mk

@@ -6,6 +6,8 @@
 
 VTUN_VERSION = 3.0.3
 VTUN_SITE = http://downloads.sourceforge.net/project/vtun/vtun/$(VTUN_VERSION)
+VTUN_LICENSE = GPLv2+ with OpenSSL exception
+VTUN_LICENSE_FILES = README.OpenSSL
 VTUN_DEPENDENCIES = host-bison host-flex zlib lzo openssl
 VTUN_AUTORECONF = YES