package/alsamixergui: add license information

Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/alsamixergui/alsamixergui.mk

@@ -7,6 +7,8 @@
 ALSAMIXERGUI_VERSION = 0.9.0rc2-1
 ALSAMIXERGUI_SOURCE = alsamixergui_$(ALSAMIXERGUI_VERSION).orig.tar.gz
 ALSAMIXERGUI_SITE = http://snapshot.debian.org/archive/debian/20141023T043132Z/pool/main/a/alsamixergui
+ALSAMIXERGUI_LICENSE = GPLv2+
+ALSAMIXERGUI_LICENSE_FILES = debian/copyright
 ALSAMIXERGUI_AUTORECONF = YES
 
 ALSAMIXERGUI_CONF_ENV = \