libfdt: migrate fdt_wip.c to a wrapper of scripts/dtc/libfdt/fdt_wip.c

Now, lib/libfdt/fdt_wip.c is the same as scripts/dtc/libfdt/fdt_wip.c

Change the former to a wrapper of the latter.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/lib/libfdt/Makefile b/lib/libfdt/Makefile
index 369bbf9..be42e94 100644
--- a/lib/libfdt/Makefile
+++ b/lib/libfdt/Makefile
@@ -8,6 +8,7 @@
 # Use upstream code.
 obj-y += \
 	fdt.o \
+	fdt_wip.o \
 	fdt_strerror.o \
 	fdt_sw.o \
 	fdt_empty_tree.o \
@@ -19,8 +20,7 @@
 # TODO: split out the local modifiction.
 obj-y += \
 	fdt_ro.o \
-	fdt_rw.o \
-	fdt_wip.o \
+	fdt_rw.o
 
 # U-Boot own file
 obj-y += fdt_region.o