gui.c: Remove silly warning on SIGINT.

gui.c: Remove silly warning on SIGINT.

Sending SIGINT to para_gui has no effect, yet we print a strange
"reset" warning in this case. This patch removes the warning and the
outdated comment which referred to do_select(), a function which was
removed long ago.

Note that (a) we still catch SIGINT, and (b) hitting CTRL+C still
causes the status task to respawn the stat process because CTRL+C
sends SIGINT to the foreground process group, which includes the
stat process.