Remove unused pylint suppressions

pylint is not used since bb5b1a0. The pyflakes cleanup mentioned in that
commit has not been done, but given that this project is no longer being
actively developed I don't think it's worth spending time doing it.

Leaving the pylint suppressions causes confusion because it leads people
to think that we are still using pylint.

Change-Id: If7d9f280a0f408c780f15915ffdb80579ae21f69
diff --git a/manifest_xml.py b/manifest_xml.py
index d0211ea..81a6a85 100644
--- a/manifest_xml.py
+++ b/manifest_xml.py
@@ -483,8 +483,7 @@
       raise ManifestParseError("no <manifest> in %s" % (path,))
 
     nodes = []
-    for node in manifest.childNodes:  # pylint:disable=W0631
-                                      # We only get here if manifest is initialised
+    for node in manifest.childNodes:
       if node.nodeName == 'include':
         name = self._reqatt(node, 'name')
         fp = os.path.join(include_root, name)