Bluetooth: Handle invalid BT service while getting the BT state

Introduced the sleep for 1 sec in case of Bluetooth service
is null while getting the Bluetooth state.

This will make sure to get the valid bluetooth service, and when
next time getState is being called, a proper BT state is returned
to the caller.

Change-Id: If126f4cda5cfe33fda4c645a9d10acbf8459efcc
CRs-Fixed: 594039