i40e: Make it clear a parameter is never used

i40e: Make it clear a parameter is never used

Orabug: 22342532

Flag the filter_mask parameter as __always_unused in the
ndo_bridge_getlink function.

Change-ID: Ifc1e99c7fb84bcbf81cf7b0ac891ad8ca956ffb2
Signed-off-by: Carolyn Wyborny <carolyn.wyborny@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
(cherry picked from commit 9f4ffc4426c4a4b6d4a84413e13efba6a72bf81d)
Signed-off-by: Brian Maly <brian.maly@oracle.com>
Conflicts:
	drivers/net/ethernet/intel/i40e/i40e_main.c