arm64: core: force data synchronization between context switch

[schouleur-sc]

This patch fixes memory corruption that can happen when running in multi-thread and multi-core environment with heavy scheduling stress.

In SMP configuration, we must ensure that all thread's context is stored before writing the switch_handle flag. Otherwise some of the thread context writes could be delayed after another CPU begins to schedule this thread which could lead to memory corruptions.

[github-actions]

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[schouleur-sc]

Hi, can we merge this?
Thanks
Sylvain

[github-actions]

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