dt-bindings: arm: fsl-scu: add imx8qm pinctrl support

Update binding doc to support imx8qm pinctrl.

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Stefan Agner <stefan@agner.ch>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: devicetree@vger.kernel.org
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt

@@ -96,13 +96,16 @@ Pinctrl bindings based on SCU Message Protocol
 This binding uses the i.MX common pinctrl binding[3].
 
 Required properties:
-- compatible:		Should be "fsl,imx8qxp-iomuxc".
+- compatible:		Should be one of:
+			"fsl,imx8qm-iomuxc",
+			"fsl,imx8qxp-iomuxc".
 
 Required properties for Pinctrl sub nodes:
 - fsl,pins:		Each entry consists of 3 integers which represents
 			the mux and config setting for one pin. The first 2
 			integers <pin_id mux_mode> are specified using a
 			PIN_FUNC_ID macro, which can be found in
+			<dt-bindings/pinctrl/pads-imx8qm.h>,
 			<dt-bindings/pinctrl/pads-imx8qxp.h>.
 			The last integer CONFIG is the pad setting value like
 			pull-up on this pin.