binman: Allow listing the entries in an image

It is useful to be able to summarise all the entries in an image, e.g. to
display this to this user. Add a new ListEntries() method to Entry, and
set up a way to call it through the Image class.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/binman/image.py b/tools/binman/image.py
index 6339d02..6f4bd5d 100644
--- a/tools/binman/image.py
+++ b/tools/binman/image.py
@@ -162,3 +162,13 @@
                   file=fd)
             self._section.WriteMap(fd, 0)
         return fname
+
+    def BuildEntryList(self):
+        """List the files in an image
+
+        Returns:
+            List of entry.EntryInfo objects describing all entries in the image
+        """
+        entries = []
+        self._section.ListEntries(entries, 0)
+        return entries