Revert "kbuild: remove unused dtc-version.sh script"

We need this to make building dtc optional. It makes no sense to build our
own dtc if the system one works correctly.

This reverts commit ddb87a0b.
Signed-off-by: NSimon Glass <sjg@chromium.org>

MAINTAINERS

@@ -756,6 +756,7 @@ F:	include/fdt*
 F:	include/linux/libfdt*
 F:	cmd/fdt.c
 F:	common/fdt_support.c
+F:	scripts/dtc-version.sh
 
 FREEBSD
 M:	Rafal Jaworowski <raj@semihalf.com>

scripts/Kbuild.include

@@ -148,6 +148,7 @@ cc-ifversion = $(shell [ $(cc-version) $(1) $(2) ] && echo $(3) || echo $(4))
 
 # added for U-Boot
 binutils-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/binutils-version.sh $(AS))
+dtc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/dtc-version.sh $(DTC))
 
 # cc-ldoption
 # Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both)

scripts/dtc-version.sh

+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0+
+#
+# dtc-version dtc-command
+#
+# Prints the dtc version of `dtc-command' in a canonical 6-digit form
+# such as `010404'  for dtc 1.4.4
+#
+
+dtc="$*"
+
+if [ ${#dtc} -eq 0 ]; then
+	echo "Error: No dtc command specified."
+	printf "Usage:\n\t$0 <dtc-command>\n"
+	exit 1
+fi
+
+MAJOR=$($dtc -v | head -1 | awk '{print $NF}' | cut -d . -f 1)
+MINOR=$($dtc -v | head -1 | awk '{print $NF}' | cut -d . -f 2)
+PATCH=$($dtc -v | head -1 | awk '{print $NF}' | cut -d . -f 3 | cut -d - -f 1)
+
+printf "%02d%02d%02d\\n" $MAJOR $MINOR $PATCH