scsi: bfa: remove bfa_fcs_mod_s

Just call the functions directly instead of obsfucating the call chain.
This was in reply to a patch from Kees Cook to constify the function
pointer struct bfa_fcs_mod_s, but it turns out there is no reason to
have this indirection at all.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>