selftests: bonding: add vlan over bond testing

Add a vlan over bond testing to make sure arp/ns target works.
Also change all the configs to mudules.

Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Link: https://patch.msgid.link/20250916080127.430626-2-liuhangbin@gmail.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>