Fix unitialized fields in htlc_out constructed from wallet database entry

wallet/wallet.c

@@ -1055,6 +1055,9 @@ static bool wallet_stmt2htlc_out(const struct wallet_channel *channel,
 	 * htlcs, will wire using origin_htlc_id */
 	out->in = NULL;
 
+	out->pay_command = NULL;
+	out->payment = NULL;
+
 	return ok;
 }