ARM: dts: remove unnecessary propery on spi_1

Change-Id: I5b6fded88df4cb4da0d93a3d4df64b669defdc5e
Signed-off-by: Dongjin Kim <tobetter@gmail.com>

arch/arm/boot/dts/exynos5422-odroidxu3.dts

@@ -505,8 +505,7 @@
 
 	spi_1: spi@12d30000 {
 	    status = "okay";
-        samsung,spi-src-clk = <0>;
-    };
+        };
 
 	spi_2: spi@12d40000 {
 		status = "disabled";