clearfog: U-Boot changes

This also updates U-Boot to 2018.01. Among other things, it makes the
USB-3 front port available, and mass storage works, yay!

Here's how I made `kwboot` available, BTW, for UART booting. It was run
in a fresh checkout of the current U-Boot's master:

  export PATH=/home/jkt/work/prog/_build/br-cfb/host/bin:$PATH
  make CROSS_COMPILE=arm-linux-gnueabihf- clearfog_defconfig
  make CROSS_COMPILE=arm-linux-gnueabihf- tools
  make CROSS_COMPILE=arm-linux-gnueabihf- -j4
  ./tools/kwboot -b ./u-boot-spl.kwb -t -p /dev/ttyUSB0

Change-Id: I97e8e7e0e775ea9383df630be043023386c5198f
diff --git a/board/czechlight/clearfog/copy-boot-scr.sh b/board/czechlight/clearfog/copy-boot-scr.sh
new file mode 100755
index 0000000..ff22ebd
--- /dev/null
+++ b/board/czechlight/clearfog/copy-boot-scr.sh
@@ -0,0 +1,3 @@
+#!/bin/sh
+
+install -m 0644 -D $BINARIES_DIR/boot.scr $TARGET_DIR/boot/boot.scr