This is incomplete [1]. If you rename a conffile, you also need to add
preinst/postinst code to do the rename on upgrades, otherwise you will
end up with *both* wine.conf (orphaned conffile) and 30-wine.conf (the
new one). Worse, if the admin previously changed wine.conf, you now
have contradictory configurations and one (probably wine.conf) will
shadow the other.
In general, renaming conffiles should be avoided, since it is
nontrivial to get right. If it is necessary, please see [2] for
recipes and details.