wifi: mt76: check vif type before reporting cca and csa

Do not report cca and csa finish to upper layer on station type vif to
prevent warnings caused by setting beacon.

Signed-off-by: Peter Chiu <chui-hao.chiu@mediatek.com>
Signed-off-by: Shayne Chen <shayne.chen@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>