dt-bindings: dsp: fsl: Add fsl,imx8mp-dsp entry

Minimal implementation needs the same DT properties as
existing compatible strings. So, we just add the new
compatible string in the list.
Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20200409071832.2039-6-daniel.baluta@oss.nxp.comSigned-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/dsp/fsl,dsp.yaml

@@ -17,6 +17,8 @@ properties:
   compatible:
     enum:
       - fsl,imx8qxp-dsp
+      - fsl,imx8qm-dsp
+      - fsl,imx8mp-dsp
 
   reg:
     description: Should contain register location and length