RESTRICT AUTOMERGE: maxfg: add mutex while logs the latest entry during running of log_learning, capture buffer can be reset by other thread and latest_entry can be null when calls maxfg_capture_to_cstr Bug: 328065795 Change-Id: I86b1be74d6dfaa99ce571ebb6fa5e464b019e38e Signed-off-by: Chungro Lee <[email protected]>