Bluetooth: controller: Included guard for lost data in framed PDUs

Improvement for IAL/CIS/FRA/PER/BI-01-C & IAL/CIS/FRA/PER/BI-02-C
-- Test appears to fail as the transmitted PDU is packed with less data
   than is indicated in the segment headers.
-- Guards were included to verify that sufficient data exists in the PDU
   before extracting the segment.

General
-- Updated timestamps in error SDUs to better approximate the expected
   timestamps if time information is missing.

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