input: Remove edge flags

These are always set to NONE by the input subsystem.

Test: check that touchscreen and touchpad input still works, including
      for system navigation gestures
Test: $ m checkinput
Test: $ atest --host inputflinger_tests
Bug: 321101159
Flag: EXEMPT refactor

Change-Id: I32750369f815222997a461a07f39cf71f3fe3ce9