dt-bindings: arm: fsl: Add i.MX8MP FRDM board

Add device tree compatible string for the i.MX8MP FRDM board.

Acked-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Rogerio Pimentel <rpimentel.silva@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

Author: rogeriorps

Documentation/devicetree/bindings/arm/fsl.yaml

@@ -1099,6 +1099,7 @@ properties:
               - emcraft,imx8mp-navqp      # i.MX8MP Emcraft Systems NavQ+ Kit
               - fsl,imx8mp-evk            # i.MX8MP EVK Board
               - fsl,imx8mp-evk-revb4      # i.MX8MP EVK Rev B4 Board
+              - fsl,imx8mp-frdm           # i.MX8MP Freedom Board
               - gateworks,imx8mp-gw71xx-2x # i.MX8MP Gateworks Board
               - gateworks,imx8mp-gw72xx-2x # i.MX8MP Gateworks Board
               - gateworks,imx8mp-gw73xx-2x # i.MX8MP Gateworks Board