ixgbe: Fix SFP log messages

We had a wide range of log messages for the same sort of SFP
failure.  This patch makes them all more similar and less
confusing along with converting them to dev_err.

Signed-off-by: Don Skidmore <donald.c.skidmore@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>