[why]
Some sourcefonts, even that are monospaced, have a `fi` and/or `fl`
ligature that maps into one cell. That looks very strange.
[how]
Partially revert commit
148b0c445 Sunset ligature removal
for the cases that have a one-cell `fi`, `fl`, etc ligature, or a `ldot`
related ligature - that is active by default. Discretionary ligatures or
Stylistic Sets are not changed.
Do the removal on all patched fonts for consistency, not just `Nerd Font Mono`.
[note]
On Noto different subtables are needed for Sans, Serif and Sans-Mono. We
can not set up different configs for each, so all are tried in all fonts
and might fail (this is normal).
Same holds for OpenDyslexic Alta, Regular, Mono, Bold...
Fixes: #1187
Signed-off-by: Fini Jastrow <ulf.fini.jastrow@desy.de>