Introduce 6GHz channel list in mt76 module. This is a preliminary patch
to unlock 6GHz band for mt7921 devices.
Tested-by: NDeren Wu <deren.wu@mediatek.com>
Signed-off-by: NLorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: NFelix Fietkau <nbd@nbd.name>