tfm_fc: use transport_handle_cdb_direct

ft_send_work is always called from workqueue context, which means we can
handle the CDB directly instead of doing another context switch.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Kiran Patil <kiran.patil@intel.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>