[SCSI] libfc: Move non-common routines and prototypes out of libfc.h

This patch moves all non-common routines and function prototypes
out of libfc.h and into the appropriate .c files. It makes these
routines 'static' when necessary and removes any unnecessary EXPORT_SYMBOL
statements.

A result of moving the fc_exch_seq_send, fc_seq_els_rsp_send, fc_exch_alloc
and fc_seq_start_next prototypes out of libfc.h is that they were no longer
being imported into fc_exch.c when libfc.h was included. This caused errors
where routines in fc_exch.c were looking for undefined symbols. To fix this
this patch reorganizes fc_seq_alloc, fc_seq_start_next and
fc_seq_start_next_locked. This move also made it so that
fc_seq_start_next_locked did not need to be prototyped at the top of
fc_exch.c.

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