lmbench: Add license info

Add license info for lmbench.

Signed-off-by: Kelvin Cheung <keguang.zhang@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/lmbench/lmbench.mk

@@ -6,6 +6,8 @@
 LMBENCH_VERSION:=3.0-a9
 LMBENCH_SOURCE:=lmbench-$(LMBENCH_VERSION).tgz
 LMBENCH_SITE:=http://$(BR2_SOURCEFORGE_MIRROR).dl.sourceforge.net/project/lmbench/development/lmbench-3.0-a9/
+LMBENCH_LICENSE =  lmbench license (based on GPLv2)
+LMBENCH_LICENSE_FILES = COPYING COPYING-2
 
 define LMBENCH_CONFIGURE_CMDS
 	$(call CONFIG_UPDATE,$(@D))