findmissing: initdb_upstream: Don't log duplicate entries

When executing "git log" commands starting with a specific SHA, we often get
duplicates. Presumably this is because git history is not always linear across
merges.

Do not log this event as it just creates a lot of noise.

BUG=None
TEST=Run scripts on target

Change-Id: If4408b5974046b2613dce4a35640bbee63a5b94c
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/dev-util/+/2189515
Commit-Queue: Guenter Roeck <groeck@chromium.org>
Tested-by: Guenter Roeck <groeck@chromium.org>
Reviewed-by: Curtis Malainey <cujomalainey@chromium.org>
diff --git a/contrib/findmissing/initdb_upstream.py b/contrib/findmissing/initdb_upstream.py
index a1a9fd1..364328b 100755
--- a/contrib/findmissing/initdb_upstream.py
+++ b/contrib/findmissing/initdb_upstream.py
@@ -72,8 +72,11 @@
                 cursor.execute(q, [sha, description, patch_id])
                 print('Inserted sha %s into linux_upstream' % sha)
             except MySQLdb.Error as e: # pylint: disable=no-member
-                print('Issue inserting (sha, description, patch_id) %s %s %s'
-                    % (sha, description, patch_id), e)
+                # Don't complain about duplicate entries; those are seen all the time
+                # due to git idiosyncrasies (non-linearity).
+                if e.args[0] != MySQLdb.constants.ER.DUP_ENTRY:
+                    print('Issue inserting (sha, description, patch_id) %s %s %s'
+                            % (sha, description, patch_id), e)
                 continue
             except UnicodeEncodeError as e:
                 print('Failed to INSERT upstream sha %s with description %s'