LU-7569 o2iblnd: avoid intensive reconnecting

LU-7569 o2iblnd: avoid intensive reconnecting

When there is a connection race between two nodes and one side
of the connection is rejected by the other side. o2iblnd will
reconnect immediately, this is going to generate a lot of
trashes if:

- race winner is slow and can't send out connecting request
  in short time.
- remote side leaves a cmid in TIMEWAIT state, which will reject
  future connection requests

To resolve this problem, this patch changed the reconnection
behave: reconnection is submitted by connd only if a zombie
connection is being destroyed and there is a pending
reconnection request for the corresponding peer.

Also, after a few rejections, reconnection will have a time
interval between each attempt.

Signed-off-by: Liang Zhen <liang.zhen@intel.com>
Change-Id: I45f010a27ef0b337c225a2354845db8cb6bb9969
Reviewed-on: http://review.whamcloud.com/17892
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Doug Oucharek <doug.s.oucharek@intel.com>
Reviewed-by: James Simmons <uja.ornl@yahoo.com>
Tested-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>