Add quirks for Lenovo MIIX 720.
- Lenovo MIIX 720 is a tablet with a detachable keyboard. To keep
the volume rockers on the tablet enabled even when the keyboard
is detached, add
ModelTabletModeNoSuspend=1
to the internal keyboard. - The external keyboard is a keyboard-touchpad combo. Assign
AttrTPKComboLayout=below
to the touchpad to allow features like disable-while-typing and palm-detection.