e100 parts don't support vlan offload but they generally do
allow use of vlans in higher software layers via the 8021q module.
That said, there are a couple of really old revisions of e100
hardware that don't even allow the longer frame sizes
required for vlan use with standard MTU.

Use the VLAN_CHALLENGED flag to prevent vlan binding to these
devices.
Reported-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
CC: Michael Tokarev <mjt@tls.msk.ru>
CC: David Lamparter <equinox@diac24.net>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>