dt-bindings: arm: imx: add imx8mm/imx8mn GW7902 support

The GW7902 is based on the i.MX 8M Mini / Nano SoC featuring:
 - LPDDR4 DRAM
 - eMMC FLASH
 - Gateworks System Controller
 - LTE CAT M1 modem
 - USB 2.0 HUB
 - M.2 Socket with USB2.0, PCIe, and dual-SIM
 - IMX8M FEC
 - PCIe based GbE
 - RS232/RS485/RS422 serial transceiver
 - GPS
 - CAN bus
 - WiFi / Bluetooth
 - MIPI header (DSI/CSI/GPIO/PWM/I2S)
 - PMIC

Signed-off-by: Tim Harvey <[email protected]>
Acked-by: Rob Herring <[email protected]>
Signed-off-by: Shawn Guo <[email protected]>

Documentation/devicetree/bindings/arm/fsl.yaml

@@ -712,6 +712,7 @@ properties:
               - gw,imx8mm-gw72xx-0x       # i.MX8MM Gateworks Development Kit
               - gw,imx8mm-gw73xx-0x       # i.MX8MM Gateworks Development Kit
               - gw,imx8mm-gw7901          # i.MX8MM Gateworks Board
+              - gw,imx8mm-gw7902          # i.MX8MM Gateworks Board
               - kontron,imx8mm-n801x-som  # i.MX8MM Kontron SL (N801X) SOM
               - variscite,var-som-mx8mm   # i.MX8MM Variscite VAR-SOM-MX8MM module
           - const: fsl,imx8mm
@@ -742,6 +743,7 @@ properties:
               - beacon,imx8mn-beacon-kit  # i.MX8MN Beacon Development Kit
               - fsl,imx8mn-ddr4-evk       # i.MX8MN DDR4 EVK Board
               - fsl,imx8mn-evk            # i.MX8MN LPDDR4 EVK Board
+              - gw,imx8mn-gw7902          # i.MX8MM Gateworks Board
           - const: fsl,imx8mn
 
       - description: Variscite VAR-SOM-MX8MN based boards