dt-bindings: timer: Add fsl,vf610-pit.yaml

Add binding doc fsl,vf610-pit.yaml to fix below CHECK_DTB warnings:

arch/arm/boot/dts/nxp/vf/vf610m4-colibri.dtb:
  /soc/bus@40000000/pit@40037000: failed to match any schema with compatible: ['fsl,vf610-pit']

Signed-off-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20250522205710.502779-1-Frank.Li@nxp.com


Signed-off-by: Rob Herring (Arm) <robh@kernel.org>