Make time not inline on unsupported platforms

[quininer]

The PR main intention is to allow enable wasm support in std time (see #48564) with minimal changes via binary patches. but since the now function is inlined, it is not work at the moment. this PR marks it as #[inline(never)] to make it patchable.

I have tested the patch and it works.

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[bjorn3]

#[inline(never)] still allows LLVM to modify the ABI in ways that prevent binary patching. For example if it notices that the function never writes to the return area, it can remove the return area pointer on both the caller and callee side (deadargelim). It can also notice that the function never returns and place an unreachable after the call or do a tail call. #[inline(never)] only disables inlining (though even this is not guaranteed), not other interprocedural optimizations.

[ChrisDenton]

I think a discussion needs to happen before making a PR. If we do want to add hooks (vs. just making a target with time support) then I do not think this PR is the right way to do it for the reasons bjorn3 outlines above.

Please open an issue to discuss the proposal in more depth.

[quininer]

@bjorn3 This is a good point, and I was aware of it before open PR. but I don't know how to avoid it in rust.

@ChrisDenton Sorry, I'll open an issue.

[quininer]

I don't think this will be merged, so closed