genlist: Send param item type instead of eo item type.
genlist: Send param item type instead of eo item type.

Summary:
The _item_unselect() fucntion called at _elm_genlist_select_mode_set() with parameter.
It makes crash when access it->item. it is eo item type actually so it doesn't have member as item or something.
@fix

Test Plan:
1. Run elementary_test
2. Execute genlist
3. Select an item on list and click Next API fucntion button 2times.
4. Check the crash.

Reviewers: seoz, woohyun, Hermet

Reviewed By: Hermet

Subscribers: SanghyeonLee

Differential Revision: https://phab.enlightenment.org/D2136

tasn/elementary,FlorentRevest/Elementary,tasn/elementary,FlorentRevest/Elementary,rvandegrift/elementary,tasn/elementary,FlorentRevest/Elementary,tasn/elementary,rvandegrift/elementary,FlorentRevest/Elementary,rvandegrift/elementary,tasn/elementary,rvandegrift/elementary