arm64: dts: imx93-9x9-qsb: change usdhc tuning step for eMMC and SD

During system resume, the following errors occurred:

  [  430.638625] mmc1: error -84 writing Cache Enable bit
  [  430.643618] mmc1: error -84 doing runtime resume

For eMMC and SD, there are two tuning pass windows and the gap between
those two windows may only have one cell. If tuning step > 1, the gap may
just be skipped and host assumes those two windows as a continuous
windows. This will cause a wrong delay cell near the gap to be selected.

Set the tuning step to 1 to avoid selecting the wrong delay cell.

For SDIO, the gap is sufficiently large, so the default tuning step does
not cause this issue.

Fixes: 0565d20cd8 ("arm64: dts: freescale: Support i.MX93 9x9 Quick Start Board")
Signed-off-by: Luke Wang <ziniu.wang_1@nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>

arch/arm64/boot/dts/freescale/imx93-9x9-qsb.dts

@@ -507,6 +507,7 @@ &usdhc1 {
 	pinctrl-2 = <&pinctrl_usdhc1_200mhz>;
 	bus-width = <8>;
 	non-removable;
+	fsl,tuning-step = <1>;
 	status = "okay";
 };
 
@@ -519,6 +520,7 @@ &usdhc2 {
 	vmmc-supply = <&reg_usdhc2_vmmc>;
 	bus-width = <4>;
 	no-mmc;
+	fsl,tuning-step = <1>;
 	status = "okay";
 };