dt-bindings: pinctrl: apple,pinctrl: Add t8122 compatible

dt-bindings: pinctrl: apple,pinctrl: Add t8122 compatible

The pin controller on the Apple silicon t8122 (M3) SoC is compatible
with the existing driver. Add "apple,t8122-pinctrl" as SoC specific
compatible under "apple,t8103-pinctrl" used by the driver.

Signed-off-by: Janne Grunau <j@jannau.net>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Reviewed-by: Linus Walleij <linusw@kernel.org>
Reviewed-by: Neal Gompa <neal@gompa.dev>
Reviewed-by: Joshua Peisach <jpeisach@ubuntu.com>
Signed-off-by: Linus Walleij <linusw@kernel.org>