[SCSI] libfc: During fabric logoff, flush the rport Q after logging off dns port

We want to generate the rport queue event (from the logoff)
before flushing the queue otherwise the event may still be
in the queue when we logoff.

Signed-off-by: Abhijeet Joglekar <abjoglek@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>