dt-bindings: interrupt-controller: apple,aic2: Add apple,t8112-aic compatible

The Apple M2 SoC uses AICv2 and is compatible with the existing driver.
Add its per-SoC compatible.
Since multi-die versions of the M2 are not expected decrease
'#interrupt-cells' to 3 for apple,t8112-aic. This is seamlessly handled
inside the driver.

Acked-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Janne Grunau <j@jannau.net>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Hector Martin <marcan@marcan.st>