package/rpi-firmware: add license hash

Signed-off-by: Adam Duskett <Aduskett@gmail.com>
[Arnout: fix path to license file]
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>

package/rpi-firmware/rpi-firmware.hash

@@ -1,2 +1,3 @@
 # Locally computed
 sha256 e911f6342ea8aa9380cae97c6f5ac4ddd370527265f23d5b5d4b2c6f679d4ba8 rpi-firmware-ebf7b40cdc6effe7ffa3fd5195e8be01b94f80da.tar.gz
+sha256 ba76edfc10a248166d965b8eaf320771c44f4f432d4fce2fd31fd272e7038add boot/LICENCE.broadcom