Allow use of oslo.messaging 1.2.0a11

Since a11:

 1806c07 Remove check_for_lock support in RPCClient
 f7cf853 Don't include msg_id or reply_q in casts
 aebe53f Fix race-condition in rabbit reply processing
 59299dc Fix error message if message handler fails

Change-Id: Ic55d4214ff091456e33a028b584bab340c30eab0
Merge "Allow use of oslo.messaging 1.2.0a11"