patman: Refactor how the default subcommand works

At present patman tries to assume a default subcommand of 'send', to
maintain backwards compatibility. However it does not cope with
arguments added to the default command, so for example 'patman -t'
does not work.

Update the logic to handle this. Also update the CC command to use 'send'
explicitly, since otherwise patman gets confused with the patch-filename
argument.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/patman/func_test.py b/tools/patman/func_test.py
index e2adf32..5933fcf 100644
--- a/tools/patman/func_test.py
+++ b/tools/patman/func_test.py
@@ -248,7 +248,7 @@
         self.assertEqual('      Cc:  %s' % rick, next(lines))
         expected = ('Git command: git send-email --annotate '
                     '--in-reply-to="%s" --to "u-boot@lists.denx.de" '
-                    '--cc "%s" --cc-cmd "%s --cc-cmd %s" %s %s'
+                    '--cc "%s" --cc-cmd "%s send --cc-cmd %s" %s %s'
                     % (in_reply_to, stefan, sys.argv[0], cc_file, cover_fname,
                        ' '.join(args)))
         self.assertEqual(expected, tools.ToUnicode(next(lines)))