liburcu: define license

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

package/liburcu/liburcu.mk

@@ -7,6 +7,8 @@
 LIBURCU_VERSION = 0.7.7
 LIBURCU_SITE    = http://lttng.org/files/urcu/
 LIBURCU_SOURCE  = userspace-rcu-$(LIBURCU_VERSION).tar.bz2
+LIBURCU_LICENSE = LGPLv2.1+ for the library; MIT-like license for few source files listed in LICENSE
+LIBURCU_LICENSE_FILES = lgpl-2.1.txt lgpl-relicensing.txt LICENSE
 
 LIBURCU_INSTALL_STAGING = YES