wl12xx: handle dummy packet event also in ap mode

Allow handling of DUMMY_PACKET_EVENT_ID also in ap mode.

Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>