fcoe: fix the link error status block sparse warnings

Both fcoe_fc_els_lesb and fc_els_lesb are in __be32 already, and both are
exactly the same size in bytes, with somewhat different member names to
reflect the fact the former is for Ethernet media the latter is for Fiber
Channel, so, remove conversion and use __be32 directly. This fixes the warning
from sparse check.

Signed-off-by: Yi Zou <yi.zou@intel.com>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Tested-by: Jack Morgan <jack.morgan@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>