Fix Lvol connect API response

[boddumanohar]

return the actual error message as a part of the response API

Without this change this is what we see on the CSI driver side

oner is provisioning volume for claim "default/spdkcsi-pvc"
  Warning  ProvisioningFailed    4s (x5 over 11s)  csi.simplyblock.io_manohar-exra-node-1_b19c2b1d-d063-492f-a7bd-e76027ac06d0  failed to provision volume with StorageClass "simplyblock-simplyblock-cluster-pool4": rpc error: code = Internal desc = json: cannot unmarshal bool into Go value of type []*util.LvolConnectResp

Now this is the response

{"error":"Volume 4f533b12-dedc-452d-afaf-a507acce6705 has allowed hosts configured; --host-nqn is required","results":[],"status":false}