Ensure numeric values are passed for possibly None attributes (#131)

Author: puddly

zigpy_xbee/zigbee/application.py

@@ -221,8 +221,8 @@ async def send_packet(self, packet: zigpy.types.ZigbeePacket) -> None:
         send_req = self._api.tx_explicit(
             long_addr,
             short_addr,
-            packet.src_ep,
-            packet.dst_ep,
+            packet.src_ep or 0,
+            packet.dst_ep or 0,
             packet.cluster_id,
             packet.profile_id,
             packet.radius,