Bluetooth: controller: Use consecutive event for framed TX and RX bugfix

Changes:
-- Disregards target event after segmenting the first TX SDU and instead
   decide event based on the next payload and feasibility to fragment
   for that event (time-offset > 0)
-- Corrected error SDU release logic when an error occurs while
   expecting the start of a new SDU, to avoid releasing an SDU which
   could be received in the next payload or event
-- Included additional debug logging

Signed-off-by: Nirosharn Amarasinghe <niag@demant.com>