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/colibri_t20_defconfig b/configs/colibri_t20_defconfig
index 8987567..5f19b55 100644
--- a/configs/colibri_t20_defconfig
+++ b/configs/colibri_t20_defconfig
@@ -3,3 +3,4 @@
 CONFIG_TEGRA20=y
 CONFIG_TARGET_COLIBRI_T20=y
 CONFIG_DEFAULT_DEVICE_TREE="tegra20-colibri"
+CONFIG_CMD_SETEXPR=y