dt-bindings: reset: Add Starfive JH7100 reset bindings

Add bindings for the reset controller on the JH7100 RISC-V SoC by
StarFive Ltd. This is a test chip for their upcoming JH7110 SoC.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>