dt-bindings: arm: ti: Add compatible for AM642-based TQMaX4XxL SOM family and carrier board

For now only the MBaX4Xx carrier board is defined.

Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/e4283d6af59c77d2f690e070eb948dd9142a2276.1690463382.git.matthias.schiffer@ew.tq-group.com


Signed-off-by: Nishanth Menon <nm@ti.com>