fm10k: Remove redundant rx_errors in ethtool

Output of ethtool was reporting 2 rx_errors entries. This change
removes one of the redundant entries.

Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Acked-by: Matthew Vick <matthew.vick@intel.com>
Tested-by: Krishneil Singh <krishneil.k.singh@intel.com>