dt-bindings: timer: Add StarFive JH7100 clint

Add compatible string for the StarFive JH7100 clint.

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