[SCSI] libfcoe: rename libfcoe.c to fcoe_cltr.c for the coming fcoe_transport.c

The existing libfcoe.c is mostly for FIP support, rename it to reflect that
fact and so we can add fcoe_transport.c to the make file to include both
into the libfcoe kernel module.

[ Minor modifications by Robert Love converting a few
  "__attribute__((packed))" modifiers to "__packed" to remove new
  checkpatch.pl WARNINGS ]

Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>