Add --no-cover and -o - to output to stdout

By request, provide a way to output the results of b4 am to stdout. This
way it can be piped straight to "git am".

E.g.:
  b4 diff 20200526205322.23465-1-mic@digikod.net -o - | git am

Requested-by: Rob Herring <robh@kernel.org>
Signed-off-by: Konstantin Ryabitsev <konstantin@linuxfoundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/b4/diff.py b/b4/diff.py
index 33a8b0c..7e9125b 100644
--- a/b4/diff.py
+++ b/b4/diff.py
@@ -57,7 +57,7 @@ def diff_same_thread_series(cmdargs):
         lmbx.add_message(msg)
 
     mbx.close()
-    os.unlink(mboxfile)
+    os.unlink(savefile)
 
     if wantvers and len(wantvers) == 1:
         upper = max(lmbx.series.keys())