bug#30190: 27.0.50; term run in line mode shows user passwords

[Noam Postavsky]

Stefan Monnier <monnier@IRO.UMontreal.CA> writes:

>> -    (setq str (term-read-noecho "Non-echoed text: " t)))
>> +    (setq str (read-passwd "Non-echoed text: ")))
>
> I believe this remove the last use of term-read-noecho, so I think we
> can then get rid of it (or at least mark it obsolete).

Makes sense.  I guess the obsoletion should go to master?

Eli, is the patch in #131 okay for emacs-26?

https://debbugs.gnu.org/cgi/bugreport.cgi?bug=30190#131