ixgbe: Do not allow LRO or MTU change with XDP

XDP does not support jumbo frames or LRO.  These checks are being made
outside the driver when an XDP program is loaded, however, there is
nothing preventing these from changing after an XDP program is loaded.
Add the checks so that while an XDP program is loaded, do not allow MTU
to be changed or LRO to be enabled.

Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>