wifi: mt76: mt7996: add EHT capability init

Add EHT mac and phy capability init for mt7996 chipsets.

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