[latexrefman] Change legend for list picture

[Karl Berry]

    > @math{@code{\somepenalty} < 10000}

    This is exactly what I mean.  I found that the text inside @code is
    in italics.

Please send failing code. It works for me. texinfo.tex 2018-02-12.17
(available from ftp.gnu.org), but I would hope it has worked all along.

However, I forgot that it is necessary to double the backslash inside
@math (because \ is itself an escape character, like @, inside @math --
though nowhere else in Texinfo).  Thus, this four-line file:

\input texinfo
@setfilename mathcode.info
@math{@code{\\somepenalty} < 10000}
@bye

ends up with the expected output for me -- "\somepenalty < 10000",
with "\somepenalty" in typewriter, with a real $<$ sign, spaced for math. -k