Elementary: fix makefile ignore efl_ui_theme edc's change

Elementary: fix makefile ignore efl_ui_theme edc's change

Summary:
When edc files in "data/elementary/themes/edc/efl" is changed,
but Makefile doesn't make new "data/elementary/themes/default.edj".
So if you want to check edc changes, delete default.edj files and do make again.

@fix

Test Plan:
1. edit edc file in "data/elementary/themes/edc/efl"
2. do "make"
3. check "data/elementary/themes/default.edj" is changed

Reviewers: jpeg, woohyun, cedric

Reviewed By: jpeg

Subscribers: taxi2se

Differential Revision: https://phab.enlightenment.org/D5691