dt-bindings: arm: apple: apple,pmgr: Add t8112-pmgr compatible

The block on Apple M2 SoCs is compatible with the existing driver so
just add its per-SoC compatible.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Janne Grunau <j@jannau.net>
Signed-off-by: Hector Martin <marcan@marcan.st>