binman: Add a SetCalculatedProperties() method

Once binman has packed the image, the position and size of each entry is
known. It is then possible for binman to update the device tree with these
positions. Since placeholder values have been added, this does not affect
the size of the device tree and therefore the packing does not need to be
performed again.

Add a new SetCalculatedProperties method to handle this.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/binman/entry.py b/tools/binman/entry.py
index 62e65c9..6a173e6 100644
--- a/tools/binman/entry.py
+++ b/tools/binman/entry.py
@@ -130,6 +130,17 @@
         self.align_end = fdt_util.GetInt(self._node, 'align-end')
         self.pos_unset = fdt_util.GetBool(self._node, 'pos-unset')
 
+    def AddMissingProperties(self):
+        """Add new properties to the device tree as needed for this entry"""
+        for prop in ['pos', 'size']:
+            if not prop in self._node.props:
+                self._node.AddZeroProp(prop)
+
+    def SetCalculatedProperties(self):
+        """Set the value of device-tree properties calculated by binman"""
+        self._node.SetInt('pos', self.pos)
+        self._node.SetInt('size', self.size)
+
     def ProcessFdt(self, fdt):
         return True