[16][RFR][s]:8252835:Revert fix for JDK-8246051

[Wang Zhuo(Zhuoren)]

As discussed before, this patch is to revert JDK-8246051(SIGBUS by unaligned Unsafe compare_and_swap). Please review.
JDK bug: https://bugs.openjdk.java.net/browse/JDK-8252835
Patch: http://cr.openjdk.java.net/~wzhuo/8252835/webrev.00/


Regards,
Zhuoren