This augments the PL08x bindings to include the Faraday Technology
FTDMAC020 DMA engine, as it is clearly a derivative of the PL08x
PrimeCell. Also specify that it needs the special peripheral ID
specified to work properly.

Cc: devicetree@vger.kernel.org
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>