add default overlay for END_CALL_BEHAVIOR

- for automotive, default END_CALL_BEHAVIOR should be 0.
- automotive product should have overlay overriding it.
- default value is the same as now

bug: 31926624
Test: manual (check dumpsys window policy)
Change-Id: Ice7b3c1374dfccf8a03c13c73201fa1615acab5f