bitbake: siggen: Ensure new unihash propagates through the system

Its possible the new unihash may not exist in sstate. Currently the code
would create an sstate object with the old hash however this updates it to
create the object with the new unihash.

(Bitbake rev: abcaa1398031fa5338a43859c661e6d4a9ce863d)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/siggen.py

@@ -513,6 +513,7 @@ class SignatureGeneratorUniHashMixIn(object):
                     bb.debug(1, 'Task %s unihash changed %s -> %s by server %s' % (taskhash, unihash, new_unihash, self.server))
                     bb.event.fire(bb.runqueue.taskUniHashUpdate(fn + ':do_' + task, new_unihash), d)
                     self.set_unihash(tid, new_unihash)
+                    d.setVar('BB_UNIHASH', new_unihash)
                 else:
                     bb.debug(1, 'Reported task %s as unihash %s to %s' % (taskhash, unihash, self.server))
             except hashserv.client.HashConnectionError as e: