arm64: zynqmp: Describe bus-width for SD card on KV260

SD card is connected with 4 data lines which should be described properly.

Signed-off-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/065cb9f1c6706eb4d70066e25cfc30d17b9f875d.1695378830.git.michal.simek@amd.com
diff --git a/arch/arm/dts/zynqmp-sck-kv-g-revB.dtso b/arch/arm/dts/zynqmp-sck-kv-g-revB.dtso
index 1b1d9e7..44738ce 100644
--- a/arch/arm/dts/zynqmp-sck-kv-g-revB.dtso
+++ b/arch/arm/dts/zynqmp-sck-kv-g-revB.dtso
@@ -144,7 +144,7 @@
 	clk-phase-uhs-sdr25 = <120>, <60>;
 	clk-phase-uhs-ddr50 = <126>, <48>;
 	assigned-clock-rates = <187498123>;
-	bus-width = <8>;
+	bus-width = <4>;
 };
 
 &gem3 {