RDMA/nes: Abnormal listener exit causes loopback node crash

When the listener is destroyed for a loopback connection, the listener
node gets a reset event.  This causes a crash as the listener is not
expecting a reset event.  Code review of cm_event_reset() during
debugging showed the cm_id ref count is incremented after calling its
event handler and not before.

Signed-off-by: Faisal Latif <faisal.latif@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>