fix small python bug in database processing code
fix small python bug in database processing code

util/stats/db.py:
    fix usage of hasattr

haowu4682/gem5,andrewfu0325/gem5-aladdin,andrewfu0325/gem5-aladdin,haowu4682/gem5,LingxiaoJIA/gem5,haowu4682/gem5,andrewfu0325/gem5-aladdin,LingxiaoJIA/gem5,LingxiaoJIA/gem5,haowu4682/gem5,LingxiaoJIA/gem5,andrewfu0325/gem5-aladdin,andrewfu0325/gem5-aladdin,andrewfu0325/gem5-aladdin,haowu4682/gem5,LingxiaoJIA/gem5,haowu4682/gem5,haowu4682/gem5,andrewfu0325/gem5-aladdin,LingxiaoJIA/gem5,haowu4682/gem5,LingxiaoJIA/gem5,haowu4682/gem5