dt-bindings: pwm: hibvt: Add hi3559v100 support

Add support for hi3559v100-shub-pwm and hisilicon,hi3559v100-pwm
platforms.

Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mathieu Othacehe <m.othacehe@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>