Escaping quote marks is only needed in attributes, not text.

```console
$ du -hs doc-old/ doc-new/
670M    doc-old/
669M    doc-new/
```

…=GuillaumeGomez

rustdoc: do not escape quotes in body text

Escaping quote marks is only needed in attributes, not text.

```console
$ du -hs doc-old/ doc-new/
670M    doc-old/
669M    doc-new/
```

…dtwco

interpret: make numeric_intrinsic accessible from Miri

This will let us share the code of the cttz and simd_cttz intrinsics (and same for ctlz).

…r=workingjubilee,calebzulawski

portable-simd: fix test suite build

``@workingjubilee`` ``@calebzulawski`` don't we run these portable-simd tests on rustc CI? Currently they don't even build here.

…otriddle

[rustdoc] Don't generate the "Fields" heading if there is no field displayed

Fixes rust-lang#118195.

If no field is displayed, we should not generate the `Fields` heading in enum struct variants.

r? ``@notriddle``