vmxnet3: do restart on VLAN changes

At least one user reports issues with vmx interfaces after 725e4008ef,
where we default to not resetting the interface on VLAN changes. This
was on an ESXi 7.0.3 setup.

Reported by: Marcos Mendoza <mmendoza@netgate.com>
MFC after: 1 week
Sponsored by: Rubicon Communications, LLC ("Netgate")