moveconfig: Correct use of members not declared in __init__()

Fix these pylint warnings.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/moveconfig.py b/tools/moveconfig.py
index 2234f28..1dff891 100755
--- a/tools/moveconfig.py
+++ b/tools/moveconfig.py
@@ -410,6 +410,10 @@
         self.parser = KconfigParser(args, self.build_dir)
         self.state = STATE_IDLE
         self.failed_boards = set()
+        self.defconfig = None
+        self.log = ''
+        self.current_src_dir = None
+        self.proc = None
 
     def __del__(self):
         """Delete the working directory