These cause U-Boot to print a list of available commands. It doesn't break
the test, but it is best to remove them from the output.
Signed-off-by: Simon Glass <sjg@chromium.org>
It is difficult to automatically test tracing on most architectures, but
with sandbox it is easy enough to do a simple sanity check.
Signed-off-by: Simon Glass <sjg@chromium.org>