Bluetooth: Controller: ISO: BIG Complete event contains invalid/unset values

[Thalley]

Describe the bug
When the controller finished setting up the BIG, it sends a BIG Complete Event which is parsed by the host, but the event is missing some values / some values are uninitialized.

To Reproduce

1. Build and run zephyr/tests/bsim/bluetooth/host/iso/bis/tests_scripts/bis.sh with tests: Bluetooth: ISO: Add validation of broadcast info #80999
2. See error

Expected behavior
Expect that all values in the event are valid

Impact
Not insignificant as the values are expose to the application layer

Logs and console output

d_00: @00:00:00.013751  [00:00:00.013,732] <inf> bis_broadcaster: ISO Channel 0x81a689c connected
d_00: @00:00:00.013947 ERROR: (WEST_TOPDIR/zephyr/tests/bsim/bluetooth/host/iso/bis/src/bis_broadcaster.c:229): Invalid ISO interval 0x0000
d_00: @00:00:00.013947  The TESTCASE FAILED (test return code 2)

Environment (please complete the following information):

• Commit SHA or Version used: tests: Bluetooth: ISO: Add validation of broadcast info #80999

Additional context
N/A

[Thalley]

@cvinayak this also seems to be an issue for unicast: #81029 where both c to p and p to c latencies are 0.