Miri: non-deterministic floating point operations in `foreign_items` Part of [rust-lang/miri/#3555](https://github.com/rust-lang/miri/issues/3555#issue-2278914000), this pr does the `foreign_items` work. Some things have changed since rust-lang/rust#138062 and rust-lang/rust#142514. I moved the "helpers" used for creating fixed outputs and clamping operations to their defined ranges to `math.rs`. These are now also extended to handle the floating-point operations in `foreign_items`. Tests in `miri/tests/float.rs` were changed/added. Failing tests in `std` were extracted, run under miri with `-Zmiri-many-seeds=0..1000` and changed accordingly. Double checked with `-Zmiri-many-seeds`. I noticed that the C standard doesn't specify the output ranges for all of its mathematical operations; it just specifies them as: ``` Returns The sinh functions return sinh x. ``` So I used [Wolfram|Alpha](https://www.wolframalpha.com/).