tools: rpc_cloud: string format error codes

If a RPC query returns an error code, print the string version of the
code as well.

Signed-off-by: Jordan Yates <jordan@embeint.com>

Author: JordanYates

src/infuse_iot/tools/rpc_cloud.py

@@ -23,6 +23,7 @@
 from infuse_iot.credentials import get_api_key
 from infuse_iot.definitions.rpc import id_type_mapping
 from infuse_iot.util.ctypes import UINT32_MAX
+from infuse_iot.zephyr.errno import errno
 
 
 class SubCommand(InfuseCommand):
@@ -125,7 +126,8 @@ def query(self, client: Client):
         if downlink.status == DownlinkMessageStatus.COMPLETED:
             rpc_rsp = downlink.rpc_rsp
             assert isinstance(rpc_rsp, RpcRsp)
-            print(f"   Result: {rpc_rsp.return_code}")
+            extra = f" ({errno(-rpc_rsp.return_code).name})" if rpc_rsp.return_code < 0 else ""
+            print(f"   Result: {rpc_rsp.return_code}{extra}")
             if rpc_rsp.params:
                 print(json.dumps(rpc_rsp.params.additional_properties, indent=4))
             elif rpc_rsp.params_encoded: