Move ARPHRD_ETHER assertion below test assume condition

Makes saner error if device does not even support APF at all.

Test: TreeHugger
Bug: 385979701
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: Ided37893d7e0d6b03436064f44d1fa9061f0951d
1 file changed