Docs: Add table to summarize platform intrinsics support

[adpaco-aws]

Description of changes:

Adds another table to our documentation to summarize support for platform intrinsics (as of now, this is basically the same as SIMD intrinsics). This is an ongoing work, but the table will be required when we add support for bitshift intrinsics, simd_div, and simd_rem since some overflow checks won't be added because it's not clear how to, so we will just call it out there.

Resolved issues:

Towards #1148

Testing:

• How is this change tested? It's documentation.

• 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

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