RFR: JDK-8294947: Use 64bit atomics in patch_verified_entry on x86_64 [v2]

[Dmitry Samersoff]

On Fri, 11 Nov 2022 23:48:22 GMT, Vladimir Kozlov <kvn at openjdk.org> wrote:

>>> ```
>>> union {
>>>   jlong cb_long;
>>>   unsigned char code_buffer[8];
>>> } u;
>>> ```
>>> 
>> 
>> This version is fine.  It removes any question about the alignment of cb_long at the same time.
>
>> This version is fine. It removes any question about the alignment of cb_long at the same time.
> 
> I agree.

done

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PR: https://git.openjdk.org/jdk/pull/11059