[clang] [clang][bytecode] Don't memcpy() FixedPoint values (PR #123599)

[Timm Baeder via cfe-commits]

tbaederr wrote:

> Maybe worth adding a release note, especially if you can write a test that would fail without this patch?

I generally don't add change log entries for this stuff since it's an experimental, off-by-default feature.

https://github.com/llvm/llvm-project/pull/123599