Remove duplicated rb_yjit_get_stats (#5997)
rb_yjit_get_stats is defined twice in yjit.c, it only needs to be defined once.
rb_yjit_get_stats
Remove duplicated rb_yjit_get_stats (#5997)
rb_yjit_get_statsis defined twice in yjit.c, it only needs to bedefined once.