package/libsigrok: add hash for license file

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/libsigrok/libsigrok.hash

@@ -1,2 +1,3 @@
 # Locally computed
 sha256	e40fde7af98d29e922e9d3cbe0a6c0569889153fc31e47b8b1afe4d846292b9c	libsigrok-0.5.1.tar.gz
+sha256	8ceb4b9ee5adedde47b31e975c1d90c73ad27b6b165a1dcd80c7c545eb65b903	COPYING