Fixes Jansson's pack-unpack format strings in perf.c
Fixes Jansson's pack-unpack format strings in perf.c

kwlzn/watchman,nodakai/watchman,facebook/watchman,facebook/watchman,wez/watchman,kwlzn/watchman,nodakai/watchman,facebook/watchman,nodakai/watchman,wez/watchman,facebook/watchman,wez/watchman,facebook/watchman,kwlzn/watchman,wez/watchman,facebook/watchman,facebook/watchman,kwlzn/watchman,kwlzn/watchman,nodakai/watchman,nodakai/watchman,nodakai/watchman,wez/watchman,nodakai/watchman,kwlzn/watchman,facebook/watchman,nodakai/watchman,wez/watchman,facebook/watchman,wez/watchman,wez/watchman,wez/watchman,nodakai/watchman,kwlzn/watchman