lib/tlsutil: Remove hardcoded curve preferences (fixes #5940) (#5942)
lib/tlsutil: Remove hardcoded curve preferences (fixes #5940) (#5942)

They are arguable outdated and we are better off trusting the standard
library than trying to keep up with it ourselves.
imsodin/syncthing,imsodin/syncthing,syncthing/syncthing,wweich/syncthing,AudriusButkevicius/syncthing,syncthing/syncthing,syncthing/syncthing,syncthing/syncthing,wweich/syncthing,imsodin/syncthing,syncthing/syncthing,AudriusButkevicius/syncthing,AudriusButkevicius/syncthing,wweich/syncthing,imsodin/syncthing,wweich/syncthing,imsodin/syncthing,syncthing/syncthing,AudriusButkevicius/syncthing