Move setexpr to Kconfig

Another shell scripting command that has not been moved.

Moved using tools/moveconfig.py using these settings:

CMD_SETEXPR bool n y

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/configs/odroid-xu3_defconfig b/configs/odroid-xu3_defconfig
index 3f4c2cb..a95813d 100644
--- a/configs/odroid-xu3_defconfig
+++ b/configs/odroid-xu3_defconfig
@@ -1,5 +1,5 @@
 CONFIG_ARM=y
 CONFIG_ARCH_EXYNOS=y
 CONFIG_TARGET_ODROID_XU3=y
-CONFIG_DEFAULT_DEVICE_TREE="exynos5422-odroidxu3"
 # CONFIG_SYS_MALLOC_CLEAR_ON_INIT is not set
+CONFIG_DEFAULT_DEVICE_TREE="exynos5422-odroidxu3"