wifi: mt76: mt7996: fix handling mbss enable/disable

wifi: mt76: mt7996: fix handling mbss enable/disable

[ Upstream commit ded1a6d9e13a32d4e8bef0c63accf49b9415ff5f ]

When mbss was previously enabled, the TLV needs to be included when
disabling it again, in order to clear the firmware state.

Fixes: a7908d5b61e5 ("wifi: mt76: mt7996: fix non-main BSS no beacon issue for MBSS scenario")
Signed-off-by: Rex Lu <rex.lu@mediatek.com>
Signed-off-by: Shayne Chen <shayne.chen@mediatek.com>
Link: https://patch.msgid.link/20240816094635.2391-9-shayne.chen@mediatek.com
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Sasha Levin <sashal@kernel.org>