display: rework the switching on and off of the cursor

The basic idea is that the cursor is always off, except when it needs
to be on: when waiting for text input, and in a few other cases: when
something was searched and found in the help viewer, and in the file
browser when option -g is in effect.

This fixes https://savannah.gnu.org/bugs/?51923.
Reported-by: Mike Frysinger <vapier@gentoo.org>
9 files changed