core: Remvoing useless AtomicInteger from EntityAsyncTask

Removing a useless Atomic integer that is not in use
anymore, besides the decrease and incrase of the value

Change-Id: Ic7d52dc4df7e39e7059e64eb0241861f88d45fef
Signed-off-by: Yair Zaslavsky <yzaslavs@redhat.com>