test_label: marked EINA_UNUSED for unused parameters and removed unnecessary casting.
test_label: marked EINA_UNUSED for unused parameters and removed unnecessary casting.

This removed build warnings.

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