Add support for volatile_load intrinsic

[adpaco-aws]

Description of changes:

Adds support for the volatile_load intrinsic, which was disabled in #1081. We keep the same implementation but add an alignment check for the src pointer (one of the safety conditions according to the documentation)

Resolved issues:

Part of #1163

Call-outs:

Testing:

• How is this change tested? Existing regression and 2 new tests.

• 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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