Make healing magic which cures blindness also cure deafness. So,
drinking non-cursed potion of healing or any extra healing or full
healing; breathing fumes from blessed potion of healing or non-cursed
potion of extra healing or any potion of full healing; prayer reward
to cure blindness as a minor trouble. (Doesn't affect unicorn horns
which already treat deafness and blindness as two distinct troubles
that are eligible to be cured.)
More of a missing feature than a bug fix, so I listed it in the new
features section of the fixes file.