Problem: Some other options reset curswant unnecessarily when set.
(Andrew Haust)
Solution: Don't reset curswant when setting 'comments', 'commentstring'
or 'define' (zeertzjq)
fixes: vim/vim#15462closes: vim/vim#15467b026a293b1
(cherry picked from commit 0ec43cb4b5)
Problem: Setting some options changes curswant unnecessarily.
Solution: Add a P_HLONLY flag that prevents changing curswant.
(zeertzjq)
closes: vim/vim#14044fcaed6a70f
