ARM: dts: imx6qdl-tqma6: remove obsolete fsl,spi-num-chipselects

This property is unneeded and not supported by the spi-imx driver.

Signed-off-by: Matthias Schiffer <[e-mail]>
Signed-off-by: Shawn Guo <[e-mail]>

arch/arm/boot/dts/imx6qdl-tqma6.dtsi

···
 &ecspi1 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_ecspi1>;
-	fsl,spi-num-chipselects = <1>;
 	cs-gpios = <&gpio3 19 GPIO_ACTIVE_HIGH>;
 	status = "okay";