dt-bindings: clock: Add the r9a06g032-sysctrl.h file

This adds the constants necessary to use the renesas,r9a06g032-sysctrl node.

Signed-off-by: Michel Pollet <michel.pollet@bp.renesas.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>