dt-bindings: dma: fsl-edma: Convert to DT schema

Convert the eDMA controller binding to DT schema.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/20220620020002.3966343-1-peng.fan@oss.nxp.com


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