patman: Convert camel case in tools.py

Convert this file to snake case and update all files which use it.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/buildman/test.py b/tools/buildman/test.py
index 2751377..43b0121 100644
--- a/tools/buildman/test.py
+++ b/tools/buildman/test.py
@@ -607,7 +607,7 @@
 
     def testPrepareOutputSpace(self):
         def _Touch(fname):
-            tools.WriteFile(os.path.join(base_dir, fname), b'')
+            tools.write_file(os.path.join(base_dir, fname), b'')
 
         base_dir = tempfile.mkdtemp()