message: [Tests][Bug] Fix staking status in generate_pos()
  "validtime" is not returned from getstakingstatus anymore (nor it was
  needed).
diff: @@ -1013,19 +1013,24 @@ class PivxTestFramework():
  """ stakes a block using generate on nodes[node_id]"""
  assert_greater_than(len(self.nodes), node_id)
  rpc_conn = self.nodes[node_id]
  + ss = rpc_conn.getstakingstatus()
  + assert ss["walletunlocked"]
  + assert ss["mintablecoins"]
  if btime is not None:
  next_btime = btime + 60
  fStaked = False
  + failures = 0
  while not fStaked:
  try:
  rpc_conn.generate(1)
  fStaked = True
  except JSONRPCException as e:
  if ("Couldn't create new block" in str(e)):
  - # couldn't generate block. check that this node can stake
  + failures += 1
  + # couldn't generate block. check that this node can still stake (after 60 failures)
  + if failures > 60:
  ss = rpc_conn.getstakingstatus()
  - if not (ss["validtime"] and ss["haveconnections"] and ss["walletunlocked"] and
  - ss["mintablecoins"] and ss["enoughcoins"]):
  + if not (ss["walletunlocked"] and ss["mintablecoins"]):
  raise AssertionError("Node %d unable to stake!" % node_id)
  # try to stake one sec in the future
  if btime is not None:
  