argv.c, [...]: Improve manual formatting.

argv.c, [...]: Improve manual formatting.

* argv.c, asprintf.c, choose-temp.c, concat.c, cplus-dem.c,
ffs.c, fnmatch.txh, getruntime.c, make-temp-file.c,
mkstemps.c, pexecute.c, random.c, strsitnal.c, vasprintf.c:
Improve manual formatting.
* functions.texi: Regenerate.

From-SVN: r46323