dtc: import latest upstream dtc

This updates scripts/dtc to commit 317a5d9 "dtc: zero out new label
objects" from git://git.jdl.com/software/dtc.git.

This adds features such as:
* /bits/ syntax for cell data.
* Math expressions within cell data.
* The ability to delete properties or nodes.
* Support for #line directives in the input file, which allows the use of
  cpp on *.dts.
* -i command-line option (/include/ path)
* -W/-E command-line options for error/warning control.
* Removal of spew to STDOUT containing the filename being compiled.
* Many additions to the libfdt API.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Jon Loeliger <jdl@jdl.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
diff --git a/scripts/dtc/libfdt/fdt_rw.c b/scripts/dtc/libfdt/fdt_rw.c
index 8e7ec4c..24437df 100644
--- a/scripts/dtc/libfdt/fdt_rw.c
+++ b/scripts/dtc/libfdt/fdt_rw.c
@@ -289,6 +289,33 @@
 	return 0;
 }
 
+int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
+		   const void *val, int len)
+{
+	struct fdt_property *prop;
+	int err, oldlen, newlen;
+
+	FDT_RW_CHECK_HEADER(fdt);
+
+	prop = fdt_get_property_w(fdt, nodeoffset, name, &oldlen);
+	if (prop) {
+		newlen = len + oldlen;
+		err = _fdt_splice_struct(fdt, prop->data,
+					 FDT_TAGALIGN(oldlen),
+					 FDT_TAGALIGN(newlen));
+		if (err)
+			return err;
+		prop->len = cpu_to_fdt32(newlen);
+		memcpy(prop->data + oldlen, val, len);
+	} else {
+		err = _fdt_add_property(fdt, nodeoffset, name, len, &prop);
+		if (err)
+			return err;
+		memcpy(prop->data, val, len);
+	}
+	return 0;
+}
+
 int fdt_delprop(void *fdt, int nodeoffset, const char *name)
 {
 	struct fdt_property *prop;
@@ -406,6 +433,8 @@
 		struct_size = 0;
 		while (fdt_next_tag(fdt, struct_size, &struct_size) != FDT_END)
 			;
+		if (struct_size < 0)
+			return struct_size;
 	}
 
 	if (!_fdt_blocks_misordered(fdt, mem_rsv_size, struct_size)) {