fdt: Sync up with libfdt

This brings in changes up to commit f9e91a48 in the libfdt repo.
Mostly this is whitespace/minor changes. But there are a few new
features:

- fdt_size_cells() and fdt_address_cells()
- fdt_resize()

Signed-off-by: Simon Glass <sjg@chromium.org>

lib/libfdt/Makefile

@@ -5,7 +5,8 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
-COBJS-libfdt += fdt.o fdt_ro.o fdt_rw.o fdt_strerror.o fdt_sw.o fdt_wip.o fdt_empty_tree.o
+COBJS-libfdt += fdt.o fdt_ro.o fdt_rw.o fdt_strerror.o fdt_sw.o fdt_wip.o \
+	fdt_empty_tree.o fdt_addresses.o
 
 obj-$(CONFIG_OF_LIBFDT) += $(COBJS-libfdt)
 obj-$(CONFIG_FIT) += $(COBJS-libfdt)