[dvipdfmx] unknown options not reported when reading stdin

[Karl Berry]

It seems unknown options are ignored when an input file is not specified:

$ dvipdfmx -junk
[waits for input]

Instead, it would be good to fail in the same way as with an input file:
$ dvipdfmx -junk hello.dvi
dvipdfmx: Unknown option "-j"

Try "dvipdfmx --help" for more information.

(Actually, that blank line seems unnecessary, but whatever. :)
--thanks, karl.