Bluetooth: Using the eventHandler to start listener

if the intent is delayed we are directly calling
the listener which is not dynamically checking the
current state of adapter.This might create issue
if we recieve this intent when BT is not in ON
State.Eventhandler is already having this check
so using eventhandler instead of direct call.

Crs-Fixed: 956092
Change-Id: Ie5331a180f1d74e5843d5b25ded69466e0b59635