[reflist] Make destroy callback optional for obj_del_ref call

This is required to support cases when access to reflist requires
external locking and destroy callback cannot be invoked with such
lock held. In this case caller has to check return value and then
invoke destroy routine.

Change-Id: I970aa4ff5bff7f030c4a50fc8836f0bd44b8ecca
1 file changed
tree: 0cb74cdbe74bd341d74a071d70519dad7ca20a8a
  1. app/
  2. include/
  3. lib/
  4. make/
  5. platform/
  6. target/
  7. AUTHORS
  8. LICENSE