sphinx: Use test vector hop_data

The test vector no longer simply fills the hop_data with 'A', instead
we actually fill in the struct.

test/test_sphinx.c

@@ -143,7 +143,11 @@ int main(int argc, char **argv)
 		}
 
 		for (i = 0; i < num_hops; i++) {
-			memset(&hops_data[i], 'A', sizeof(hops_data[i]));
+			hops_data[i].realm = 0x00;
+			memset(&hops_data[i].channel_id, i,
+			       sizeof(hops_data[i].channel_id));
+			hops_data[i].amt_forward = i;
+			hops_data[i].outgoing_cltv = i;
 		}
 
 		struct onionpacket *res = create_onionpacket(ctx,