dt-bindings: clock: add support for lan969x

Lan969x is going to reuse the existing lan966x clock driver - document
that by adding compatible strings for the different SKU's that we
support.

Signed-off-by: Daniel Machon <daniel.machon@microchip.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20240916-lan969x-clock-v1-1-0e150336074d@microchip.com


Signed-off-by: Claudiu Beznea <claudiu.beznea@tuxon.dev>