util/lint: Add commit message parsing to checkpatch_json script

The commit message wasn't being parsed because there's no filename
associated with it in the patch output.  This change adds the "filename"
for the commit message in Gerrit for any errors that have a line number
but no filename.

calculations is intentionally misspelled as cacluations as a test.

Change-Id: Ie7a2ef06419c7090c8e44b3b734b1edf966597cc
Signed-off-by: Martin Roth <martin@coreboot.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/63031
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Elyes Haouas <ehaouas@noos.fr>

util/lint/checkpatch_json.py

@@ -10,6 +10,7 @@ OUTPUT: json format output that can be used to post comment in gerrit
 import os
 import sys
 import json
+import re
 
 data = {}
 data['comments'] = []
@@ -38,6 +39,11 @@ def parse_file(input_file):
             file_path = temp[1].split(":")[0]
             line_number = temp[1].split(":")[1]
             update_struct( file_path.strip(), msg_output, str(line_number)  )
+        elif re.search("^\d+:\Z",line) != "None" and line.startswith("#"):
+            file_path="/COMMIT_MSG"
+            line = line.replace('#', '')
+            line_number = int(line.split(":")[0]) + 2
+            update_struct( file_path.strip(), msg_output, str(line_number)  )
         else:
             continue
     fp.close()