package/gdb: add hash of licence files

Adds sha256 hash of the license files for GDB.

Signed-off-by: Thomas Bonnefille <thomas.bonnefille@bootlin.com>
Signed-off-by: Julien Olivain <ju.o@free.fr>

package/gdb/gdb.hash

@@ -5,3 +5,9 @@ sha512  0217434073023a8b8316088bf3ee95d53a1b6a7897f6269095429016a8900f9a05e130c3
 
 # Locally calculated (fetched from Github)
 sha512  3518b47d5c11d1fb478ee152bde1719363f9391db73f3b9f5491217c17742bef8ebca6a51a40302dfaa9476c5a32a8b8f70a4bf64289422dea5f750ae53ab88d  gdb-arc-2023.09-release.tar.gz
+
+# Locally calculated (fetched from gcc.gnu.org)
+sha256  231f7edcc7352d7734a96eef0b8030f77982678c516876fcb81e25b32d68564c  COPYING
+sha256  8ceb4b9ee5adedde47b31e975c1d90c73ad27b6b165a1dcd80c7c545eb65b903  COPYING3
+sha256  a853c2ffec17057872340eee242ae4d96cbf2b520ae27d903e1b2fef1a5f9d1c  COPYING3.LIB
+sha256  56bdea73b6145ef6ac5259b3da390b981d840c24cb03b8e1cbc678de7ecfa18d  COPYING.LIB