(ITS#6937) Remove --enable-proctitle and strdup(optarg)

Full_Name: Hallvard B Furuseth Version: master, 2.4.25 OS: URL: Submission from: (NULL) (129.240.6.233) Submitted by: hallvard

"configure --enable-proctitle" uses setproctitle/proctitle(), which we no longer use. So I'll remove that and liblutil/setproctitle.c. That's the default implementation, which works by overwriting argv[].

That's got to be why we have strdup(optarg) instead of just optarg all over the place. So we can drop the strdup()s, which gets rid some admittedly unimportant memory leak reports from program checkers.