sim: draining bug for fast-forwaring multiple cores fix draining bug where multiple cores hit max_insts_any_thread simultaneously
sim: draining bug for fast-forwaring multiple cores
fix draining bug where multiple cores hit max_insts_any_thread simultaneously

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
(transplanted from bdb307e8be54a5808a9af2537e9261d88de6ed1b)

LingxiaoJIA/gem5,LingxiaoJIA/gem5,LingxiaoJIA/gem5,LingxiaoJIA/gem5,LingxiaoJIA/gem5,LingxiaoJIA/gem5,LingxiaoJIA/gem5