WIP: Integrate RAUC and U-Boot

Change-Id: I699e72e3229953af62393b9a1fa199e6767aba0b
diff --git a/board/czechlight/clearfog/uboot.fragment b/board/czechlight/clearfog/uboot.fragment
new file mode 100644
index 0000000..d231b5d
--- /dev/null
+++ b/board/czechlight/clearfog/uboot.fragment
@@ -0,0 +1 @@
+CONFIG_CMD_SETEXPR=y