dt-bindings: dmaengine: Add YAML schemas for the generic DMA bindings

The DMA controllers and consumers have a bunch of generic properties that
are needed in a device tree. Add a YAML schemas for those.

Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>

Link: https://lore.kernel.org/r/20190720092607.31095-1-maxime.ripard@bootlin.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>