patman: Add all CC addresses to the cover letter

If we're sending a cover letter make sure to CC everyone that we're
CCing on each of the individual patches.

Signed-off-by: Doug Anderson <dianders@chromium.org>
diff --git a/tools/patman/patman.py b/tools/patman/patman.py
index de8314a..4181d80 100755
--- a/tools/patman/patman.py
+++ b/tools/patman/patman.py
@@ -140,7 +140,7 @@
             options.count + options.start):
         ok = False
 
-    cc_file = series.MakeCcFile(options.process_tags)
+    cc_file = series.MakeCcFile(options.process_tags, cover_fname)
 
     # Email the patches out (giving the user time to check / cancel)
     cmd = ''