binman: Correct some import statements

Some of these were not converted when binman moved to use absolute paths.
Fix them.

Also drop the import of 'test' which is a directory, not a module.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/binman/control.py b/tools/binman/control.py
index 69c36ed..60e89d3 100644
--- a/tools/binman/control.py
+++ b/tools/binman/control.py
@@ -123,7 +123,7 @@
         data extracted from the entry
     """
     global Image
-    from image import Image
+    from binman.image import Image
 
     image = Image.FromFile(image_fname)
     entry = image.FindEntryPath(entry_path)
@@ -496,7 +496,7 @@
         return 0
 
     # Put these here so that we can import this module without libfdt
-    from image import Image
+    from binman.image import Image
     from binman import state
 
     if args.cmd in ['ls', 'extract', 'replace']: