DT documentation for PWM controller added.
Signed-off-by: NWesley W. Terpstra <wesley@sifive.com>
[Atish: Compatible string update]
Signed-off-by: NAtish Patra <atish.patra@wdc.com>
Signed-off-by: NYash Shah <yash.shah@sifive.com>
Reviewed-by: NRob Herring <robh@kernel.org>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>