scsi: fc: Update Descriptor definition and add RDF and Link Integrity FPINs

scsi: fc: Update Descriptor definition and add RDF and Link Integrity FPINs

Update the FC headers for the RDF ELS and populate out the FPIN ELS and the
Link integrity FPIN payload.

RDF is used to register for diagnostic events.
FPIN is how the fabric reports a diagnostic event.

Specifically, this patch:

 - Adds the formal definition of TLV descriptors that are now used in a lot
   of the FC spec. The simplistic fc_fn_desc structure, basically no more
   than the tlv definition, is removed.

 - Small tlv helper functions are added as defines.

 - The list of known Descriptor tags (identifying the TLV) is expanded and
   a name initializer introduced.

 - The LSRI descriptor, returned in many new ELS response payloads is
   added.

 - The RDF ELS code is added, and the RDF request response structures
   added.

 - The FPIN els definition is corrected.

 - A full definition of a Link Integrity Notification descriptor is added,

[mkp: rolled in kbuild warning fix]

Link: https://lore.kernel.org/r/20200210173155.547-2-jsmart2021@gmail.com
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>