dt-bindings: firmware: arm,scmi: Add properties for i.MX95 Pinctrl OEM extensions

i.MX95 Pinctrl is managed by System Control Management Interface(SCMI)
firmware using OEM extensions. No functions, no groups are provided by
the firmware. So add i.MX95 specific properties.

To keep aligned with current i.MX pinctrl bindings, still use "fsl,pins"
for i.MX95.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Reviewed-by: Dong Aisheng <aisheng.dong@nxp.com>
Link: https://lore.kernel.org/r/20240521-pinctrl-scmi-imx95-v1-1-9a1175d735fd@nxp.com


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>