ARM: hikey: Add ATF makefile referenced by README

Rather than relying on an external URL in the README
include the Makefile in the hikey directory.
Signed-off-by: NPeter Griffin <peter.griffin@linaro.org>

board/hisilicon/hikey/build-tf.mak

+CROSS_COMPILE	:= aarch64-linux-gnu-
+output_dir	:= $(PWD)/../bin
+makejobs	:= $(shell grep '^processor' /proc/cpuinfo | sort -u | wc -l)
+makethreads	:= $(shell dc -e "$(makejobs) 1 + p")
+make_options	:= GCC49_AARCH64_PREFIX=$CROSS_COMPILE \
+		-j$(makethreads) -l$(makejobs)
+
+BL30_HIKEY	:= $(output_dir)/mcuimage.bin
+BL33_HIKEY	:= $(output_dir)/u-boot-hikey.bin
+
+.PHONY: help
+help:
+	@echo "****  Common Makefile  ****"
+	@echo "example:"
+	@echo "make -f build-tf.mak build"
+
+.PHONY: have-crosscompiler
+have-crosscompiler:
+	@echo -n "Check that $(CROSS_COMPILE)gcc is available..."
+	@which $(CROSS_COMPILE)gcc > /dev/null ; \
+	if [ ! $$? -eq 0 ] ; then \
+	   echo "ERROR: cross-compiler $(CROSS_COMPILE)gcc not in PATH=$$PATH!" ; \
+	   echo "ABORTING." ; \
+	   exit 1 ; \
+	else \
+	   echo "OK" ;\
+	fi
+
+build: have-crosscompiler FORCE
+	@echo "Build TF for Hikey..."
+	rm -rf build/
+	CROSS_COMPILE=$(CROSS_COMPILE) \
+	make all fip \
+	BL30=$(BL30_HIKEY) \
+	BL33=$(BL33_HIKEY) \
+	DEBUG=1 \
+	PLAT=hikey
+	@echo "Copy resulting binaries..."
+	cp build/hikey/debug/bl1.bin $(output_dir)/bl1-hikey.bin
+	cp build/hikey/debug/fip.bin $(output_dir)/fip-hikey.bin
+
+FORCE: