ixgbe: cleanup move setting PFQDE.HIDE_VLAN to support function.

Move setting of drop enable to support function.  This not only makes the
code more readable but is also prep for following patches that add
additional MAC support.

Signed-off-by: Don Skidmore <donald.c.skidmore@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>