Conditionally revert "Block Binder thread until incoming call process completes"

* Legacy IMS packages handling incoming calls in such a way that
  a blocked binder thread won`t allow to complete call setup,
  thus we have half dead incoming calls with unattached call session
  (caller can hear dialing tone whereas recipient got nothing)

This conditionally reverts commit 75c3dc9b.

Change-Id: I55a8f3bbca4a2b9a6bc7511e9fe2d0884a8818e5