barebox: add license information

Signed-off-by: Simon Dawson <spdawson@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

boot/barebox/barebox.mk

@@ -20,6 +20,9 @@ BAREBOX_SOURCE = barebox-$(BAREBOX_VERSION).tar.bz2
 BAREBOX_SITE = http://www.barebox.org/download/
 endif
 
+BAREBOX_LICENSE = GPLv2+
+BAREBOX_LICENSE_FILES = COPYING
+
 ifneq ($(call qstrip,$(BR2_TARGET_BAREBOX_CUSTOM_PATCH_DIR)),)
 define BAREBOX_APPLY_CUSTOM_PATCHES
 	support/scripts/apply-patches.sh $(@D) $(BR2_TARGET_BAREBOX_CUSTOM_PATCH_DIR) \