buildman: Convert camel case in cmdline.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/cmdline.py b/tools/buildman/cmdline.py
index 7918195..503c48d 100644
--- a/tools/buildman/cmdline.py
+++ b/tools/buildman/cmdline.py
@@ -9,7 +9,7 @@
 BUILDMAN_DIR = pathlib.Path(__file__).parent
 HAS_TESTS = os.path.exists(BUILDMAN_DIR / "test.py")
 
-def ParseArgs():
+def parse_args():
     """Parse command line arguments from sys.argv[]
 
     Returns:
diff --git a/tools/buildman/func_test.py b/tools/buildman/func_test.py
index bd7db1e..6b6afe7 100644
--- a/tools/buildman/func_test.py
+++ b/tools/buildman/func_test.py
@@ -252,7 +252,7 @@
             result code from buildman
         """
         sys.argv = [sys.argv[0]] + list(args)
-        options, args = cmdline.ParseArgs()
+        options, args = cmdline.parse_args()
         if brds == False:
             brds = self._boards
         result = control.do_buildman(
diff --git a/tools/buildman/main.py b/tools/buildman/main.py
index 9a1d599..70ab9a4 100755
--- a/tools/buildman/main.py
+++ b/tools/buildman/main.py
@@ -60,7 +60,7 @@
     This is the main program. It collects arguments and runs either the tests or
     the control module.
     """
-    options, args = cmdline.ParseArgs()
+    options, args = cmdline.parse_args()
 
     if not options.debug:
         sys.tracebacklimit = 0