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/func_test.py b/tools/buildman/func_test.py
index c2e0b0b..b920818 100644
--- a/tools/buildman/func_test.py
+++ b/tools/buildman/func_test.py
@@ -422,7 +422,7 @@
                 if arg.startswith('O='):
                     out_dir = arg[2:]
             fname = os.path.join(cwd or '', out_dir, 'u-boot')
-            tools.WriteFile(fname, b'U-Boot')
+            tools.write_file(fname, b'U-Boot')
             if type(commit) is not str:
                 stderr = self._error.get((brd.target, commit.sequence))
             if stderr: