Deprecate tmpnam()?

[Rik]

All,

I proposed deprecating tmpnam back in 2014 as it does the same thing as the
Matlab function tempname which we also provide.  A discussion ensued here
http://octave.1599824.n4.nabble.com/Keeping-both-tmpnam-and-tempname-td4666868.html.

Back then, tmpnam was used 189 times in Octave core and 29 times in OF
packages.  Three years later there is now only one instance of tmpnam in
core, which I am just switching over.  Is is reasonable to start the
deprecation of tmpnam with the 4.4 release?

--Rik