arm64: dts: imx8mm-venice: Fix the SPI chipselect polarity

The conversion of the spi-imx driver to use GPIO descriptors
in commit 8cdcd8ae ("spi: imx/fsl-lpspi: Convert to GPIO descriptors")
helped to detect the following SPI chipselect polarity mismatch on an
imx6q-sabresd for example:

[    4.854337] m25p80@0 enforce active low on chipselect handle

Prior to the above commit, the chipselect polarity passed via cs-gpios
property was ignored and considered active-low.

The reason for such mismatch is clearly explained in the comments inside
drivers/gpio/gpiolib-of.c:

* SPI children have active low chip selects
* by default. This can be specified negatively
* by just omitting "spi-cs-high" in the
* device node, or actively by tagging on
* GPIO_ACTIVE_LOW as flag in the device
* tree. If the line is simultaneously
* tagged as active low in the device tree
* and has the "spi-cs-high" set, we get a
* conflict and the "spi-cs-high" flag will
* take precedence.

To properly represent the SPI chipselect polarity, change it to active-low
when the "spi-cs-high" property is absent.
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-By: Tim Harvey <tharvey@gateworks.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8mm-venice-gw71xx.dtsi

@@ -57,7 +57,7 @@ reg_usb_otg1_vbus: regulator-usb-otg1 {
 &ecspi2 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_spi2>;
-	cs-gpios = <&gpio5 13 GPIO_ACTIVE_HIGH>;
+	cs-gpios = <&gpio5 13 GPIO_ACTIVE_LOW>;
 	status = "okay";
 };
 

arch/arm64/boot/dts/freescale/imx8mm-venice-gw72xx.dtsi

@@ -76,7 +76,7 @@ reg_usb_otg2_vbus: regulator-usb-otg2 {
 &ecspi2 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_spi2>;
-	cs-gpios = <&gpio5 13 GPIO_ACTIVE_HIGH>;
+	cs-gpios = <&gpio5 13 GPIO_ACTIVE_LOW>;
 	status = "okay";
 };
 

arch/arm64/boot/dts/freescale/imx8mm-venice-gw73xx.dtsi

@@ -96,7 +96,7 @@ reg_wifi_en: regulator-wifi-en {
 &ecspi2 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_spi2>;
-	cs-gpios = <&gpio5 13 GPIO_ACTIVE_HIGH>;
+	cs-gpios = <&gpio5 13 GPIO_ACTIVE_LOW>;
 	status = "okay";
 };