print current_rss info in mi_stats_print

[hardfist]

It seems mimalloc only print peak_rss(it seems kind of misleading that it use "rss" other than "peak_rss" in log https://github.com/microsoft/mimalloc/blob/main/src/stats.c#L367) in mi_stats_print, and current_rss seems also useful and worthy to print out too.