Audit: Atomic intrinsics

[adpaco-aws]

Description of changes:

1. Moves intrinsics tests under the Intrinsics folder.
2. Adds support for atomic_nand* intrinsics.
3. Adds support for atomic_singlethreadfence* intrinsics.
4. Adds missing test for atomic_cxchgweak* intrinsics.
5. Adds negative tests for missing atomic intrinsics (atomic_min*, atomic_umin*, atomic_max* and atomic_umax*).
6. Updates intrinsics table to reflect actual current status.

Resolved issues:

Resolves #790
Part of #727

Call-outs:

• Support for remaining atomic intrinsics may be added later. Min/max may have different options for implementation and I want to consider all of them before committing to one.
• One test case per variant in min/max intrinsics ensures there is not support for them (via intrinsics, hooks, etc.).

Testing:

• How is this change tested? Added and edited both positive and negative test cases to the standard regression.

• Is this a refactor change? No.

Checklist

• Each commit message has a non-empty body, explaining why the change was made
• Methods or procedures are documented
• Regression or unit tests are included, or existing tests cover the modified code
• My PR is restricted to a single feature or bugfix

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 and MIT licenses.