lttng-libust: define license

Signed-off-by: Samuel Martin <s.martin49@gmail.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/lttng-libust/lttng-libust.mk

@@ -7,6 +7,8 @@
 LTTNG_LIBUST_SITE    = http://lttng.org/files/lttng-ust/
 LTTNG_LIBUST_VERSION = 2.2.0
 LTTNG_LIBUST_SOURCE  = lttng-ust-$(LTTNG_LIBUST_VERSION).tar.bz2
+LTTNG_LIBUST_LICENSE = LGPLv2.1; GPLv2 for lttng-gen-tp and ust-ctl
+LTTNG_LIBUST_LICENSE_FILES = COPYING
 
 LTTNG_LIBUST_INSTALL_STAGING = YES
 LTTNG_LIBUST_DEPENDENCIES    = liburcu util-linux