Fix ZGP profile and endpoint handling (#235)

* Fix ZGP profile and endpoint handling

* Linter

---------

Co-authored-by: Conrad Kreyling <[email protected]>

Author: Conrad Kreyling

zigpy_znp/zigbee/application.py

@@ -692,6 +692,9 @@ def _find_endpoint(self, dst_ep: int, profile: int, cluster: int) -> int:
         if dst_ep == ZDO_ENDPOINT:
             return ZDO_ENDPOINT
 
+        if profile == zigpy.profiles.zgp.PROFILE_ID:
+            return zigpy.profiles.zgp.GREENPOWER_ENDPOINT_ID
+
         # Newer Z-Stack releases ignore profiles and will work properly with endpoint 1
         if (
             self._zstack_build_id >= 20210708