show-deferred: drop check for binary-NEW packages

The .changes file may no longer have a "Binary" field since
4c22c773 for source-only uploads.

One could look at the .dsc instead, but in the end this would need
duplicating more logic from archive.py to handle binaries not built in
Debian correctly.  Dropping the check makes binary-NEW uploads in the
deferred queue available, but that seems acceptable.