[SCSI] libfc: add set_fid function to libfc template

This is to notify the LLD when an FC_ID is assigned to the local port.

The fnic driver needs to push the assigned FC_ID to firmware.
It currently does this by intercepting the FLOGI responses, and
in order to make that code more common with FIP and NPIV, it
makes more sense to wait until the local port has completely
handled the FLOGI or FDISC response.  Also, when we fix
point-to-point FC_ID assignment, we'll need this callback as well.

Add a call to the libfc template, which is called whenever
the local port FC_ID is being assigned.  It defaults to
fc_lport_set_fid(), supplied by libfc.

As additional benefit of this function, the LLD may determine
the MAC address that caused the change by looking at the received frame.

We also print the assigned port ID as long as it isn't 0.
Setting port ID to 0 happens often in reset while retrying FLOGI,
and would be uninteresting.  This replaces the previous message
which didn't identify the host adapter instance.

patch v2 note: changed one word in a comment.  "intercepted" -> "provided".

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>