patman: Add Cover-letter-cc tag to Cc cover letter to people

The cover letter is sent to everyone who is on the Cc list for any of
the patches in the series. Sometimes it is useful to send just the cover
letter to additional people, so that they are aware of the series, but
don't need to wade through all the individual patches.

Add a new Cover-letter-cc tag for this purpose.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Doug Anderson <dianders@chromium.org>
diff --git a/tools/patman/patchstream.py b/tools/patman/patchstream.py
index 91542ad..5c2d3bc 100644
--- a/tools/patman/patchstream.py
+++ b/tools/patman/patchstream.py
@@ -42,6 +42,9 @@
 # The start of the cover letter
 re_cover = re.compile('^Cover-letter:')
 
+# A cover letter Cc
+re_cover_cc = re.compile('^Cover-letter-cc: *(.*)')
+
 # Patch series tag
 re_series = re.compile('^Series-(\w*): *(.*)')
 
@@ -153,6 +156,7 @@
         # Handle state transition and skipping blank lines
         series_match = re_series.match(line)
         commit_match = re_commit.match(line) if self.is_log else None
+        cover_cc_match = re_cover_cc.match(line)
         tag_match = None
         if self.state == STATE_PATCH_HEADER:
             tag_match = re_tag.match(line)
@@ -205,6 +209,10 @@
             self.in_section = 'cover'
             self.skip_blank = False
 
+        elif cover_cc_match:
+            value = cover_cc_match.group(1)
+            self.AddToSeries(line, 'cover-cc', value)
+
         # If we are in a change list, key collected lines until a blank one
         elif self.in_change:
             if is_blank: