LeAudio: Improve printing data types

This adds the missing operators and improves the existing ones
to pretty-print the configurations for debugging purpose.

Additionaly these string stream operator are mandatary for the upcoming
unit tests as the testing frameworks requires them to report the results.

Bug: 340400084
Test: atest --host bluetooth_le_audio_test bluetooth_le_audio_client_test bluetooth_test_broadcaster bluetooth_test_broadcaster_state_machine --verbose
Flag: EXEMPT; No functional change
Change-Id: I333af0edf6201fc9c6982b4239c97482002b5fb9