HBASE-27445 fix the result of DirectMemoryUtils#getDirectMemorySize (#4846)

Co-authored-by: huiruan <huiruan@tencent.com>
Signed-off-by: Duo Zhang <zhangduo@apache.org>
(cherry picked from commit 2f4758ee592959ee5ddd646a6769bb81a781d610)
1 file changed