[SCSI] zfcp: fix: allow more time for adapter initialization

From: Maxim Shchetynin <maxim@de.ibm.com>

Extend the time for adapter initialization: In case of protocol
status HOST_CONNECTION_INITIALIZING for the exchange config data
command do a first retry in 1 second, then double the sleep time for
each following retry until recovery exceeds 2 minutes. The old
behaviour of allowing 6 retries with .5 seconds delay between retries
was insufficient and qdio queues were shut down too erarly.

Signed-off-by: Andreas Herrmann <aherrman@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>