patman: Convert camel case in commit.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/patman/commit.py b/tools/patman/commit.py
index 5bf2b94..c331a3b 100644
--- a/tools/patman/commit.py
+++ b/tools/patman/commit.py
@@ -44,7 +44,7 @@
     def __str__(self):
         return self.subject
 
-    def AddChange(self, version, info):
+    def add_change(self, version, info):
         """Add a new change line to the change list for a version.
 
         Args:
@@ -55,7 +55,7 @@
             self.changes[version] = []
         self.changes[version].append(info)
 
-    def CheckTags(self):
+    def check_tags(self):
         """Create a list of subject tags in the commit
 
         Subject tags look like this:
@@ -78,7 +78,7 @@
                 str = m.group(2)
         return None
 
-    def AddCc(self, cc_list):
+    def add_cc(self, cc_list):
         """Add a list of people to Cc when we send this patch.
 
         Args:
@@ -86,7 +86,7 @@
         """
         self.cc_list += cc_list
 
-    def CheckDuplicateSignoff(self, signoff):
+    def check_duplicate_signoff(self, signoff):
         """Check a list of signoffs we have send for this patch
 
         Args:
@@ -99,7 +99,7 @@
         self.signoff_set.add(signoff)
         return True
 
-    def AddRtag(self, rtag_type, who):
+    def add_rtag(self, rtag_type, who):
         """Add a response tag to a commit
 
         Args: