[SCSI] fcoe: moves common FCoE library API functions to libfcoe module

Moves these functions as-is from fcoe.c to libfcoe.c, since
they're are common routines:

	- fcoe_wwn_from_mac
	- fcoe_libfc_config

Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>