Bluetooth: btusb: mediatek: add MT7922 subsystem reset

Add the support of MT7922 bluetooth subsystem reset that was called the
auto revert to self-recover from the fatal error in the controller like
the host encounters HCI cmd timeout or the controller crashes.

Co-developed-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Hao Qin <hao.qin@mediatek.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>