mke2fs: fix UI problem caused by fuzzy translations

mke2fs: fix UI problem caused by fuzzy translations

When the original message was changed from "(y, n)" to "(y, N)", this
caused the translations to be marked as "fuzzy".  For those
translations that use a different characters for yes and no --- for
example, German, which uses j and n for "ja" and "nein" --- not having
the translation can cause user confusion since the user will type 'y',
and it will be interpreted as "No", since mke2fs is expecting that the
user will type some other character, such as 'j' or 'J' for "Ja" in
the German locale.

Addresses-Debian-Bug: #856586

Signed-off-by: Theodore Ts'o <tytso@mit.edu>