arch: dts: am642-sk-u-boot: Disable main_sdhci0 DT node and define alias index 1 for main_sdhci1 node

A Wilink wireless device is connected to MMCSD0 subsystem and is not
supported in U-Boot. Therefore, disable main_sdhci0 device tree node in
U-Boot.

If main_sdhci0 device tree node is disabled then the the index of
main_sdhci1 node becomes 0 which leads to break in boot flow. Therefore,
add an alias to fix the index to 1.

Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Link: https://lore.kernel.org/r/20210726152807.22991-3-a-govindraju@ti.com
diff --git a/arch/arm/dts/k3-am642-sk-u-boot.dtsi b/arch/arm/dts/k3-am642-sk-u-boot.dtsi
index 35b49df..efbcfb3 100644
--- a/arch/arm/dts/k3-am642-sk-u-boot.dtsi
+++ b/arch/arm/dts/k3-am642-sk-u-boot.dtsi
@@ -8,6 +8,10 @@
 		stdout-path = "serial2:115200n8";
 		tick-timer = &timer1;
 	};
+
+	aliases {
+		mmc1 = &sdhci1;
+	};
 };
 
 &cbass_main{
@@ -79,6 +83,7 @@
 };
 
 &sdhci0 {
+	status = "disabled";
 	u-boot,dm-spl;
 };