[SCSI] bnx2fc: setup em for npiv port

Use fc_exch_mgr_list_clone to setup em for npiv port.

Also remove redundant vport and lport initializations.

Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Acked-by: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>