SUSPEND will not only change the return state in few
cases.
I have retested all test cases from previous 2 commits.
What is missing is timer for each Tx Event. RSC,BLO,UBL.
Its possible to loose a message from Slave via relay to Master.
If that ever occours we will not know what state we are in.
Thus we need a timer that will re-transmit a packet if
it does not get acknowledged.