Bug 15067: Follow up to fix sorting

Bug 15067: Follow up to fix sorting

It looks like C4::Languages:getLanguages relies on implicit database
order for languages. They appear to be sorted by subtag so this patch
adds that sorting to the database query to ensure the dropdown is
sorted.

Signed-off-by: Aleisha <aleishaamohia@hotmail.com>
Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>