rings: add license info

Signed-off-by: Francois Perrad <francois.perrad@gadz.org>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/rings/rings.mk

@@ -7,6 +7,7 @@
 RINGS_VERSION = 1.2.3
 RINGS_SITE = http://github.com/downloads/keplerproject/rings
 RINGS_DEPENDENCIES = lua
+RINGS_LICENSE = MIT
 
 define RINGS_BUILD_CMDS
 	$(MAKE) -C $(@D) CC="$(TARGET_CC)" CFLAGS="$(TARGET_CFLAGS) -fPIC"