./x check miri: enable check_only feature

Commit rust-lang#147526 removed the following code and replaced it with the `AllocatorMethod`. However, its input is empty, resulting in behavior inconsistent with the previous code.

```rust
  create_wrapper_function(
      tcx,
      &cx,
      &mangle_internal_symbol(tcx, "__rust_alloc_error_handler"),
      Some(&mangle_internal_symbol(tcx, alloc_error_handler_name(alloc_error_handler_kind))),
      &[usize, usize], // size, align
      None,
      true,
      &CodegenFnAttrs::new(),
  );
  ```

  resolves rust-lang#150755

./x check miri: enable check_only feature

With this, we should no longer need to turn off the default features, so we can undo rust-lang#149550.

@bjorn3 you seem to have a test setup to check if this works properly in terms of skipping all the work that should not be required -- could you test if this PR works as intended?

FWIW we could now remove `default_features` from `run_tool_check_step`. Not sure if that's worth it.

./x check miri: enable check_only feature

With this, we should no longer need to turn off the default features, so we can undo rust-lang#149550.

@bjorn3 you seem to have a test setup to check if this works properly in terms of skipping all the work that should not be required -- could you test if this PR works as intended?

FWIW we could now remove `default_features` from `run_tool_check_step`. Not sure if that's worth it.

Rollup of 11 pull requests

Successful merges:

 - #149976 (Add waker_fn and local_waker_fn to std::task)
 - #150074 (Update provider API docs)
 - #150094 (`c_variadic`: provide our own `va_arg` implementation for more targets)
 - #150164 (rustc: Fix `-Zexport-executable-symbols` on wasm)
 - #150569 (Ensure that static initializers are acyclic for NVPTX)
 - #150607 (Add amdgpu_dispatch_ptr intrinsic)
 - #150694 (./x check miri: enable check_only feature)
 - #150717 (Thread `--jobs` from `bootstrap` -> `compiletest` -> `run-make-support`)
 - #150736 (Add AtomicPtr::null)
 - #150787 (Add myself as co-maintainer for s390x-unknown-linux-musl)
 - #150789 (Fix copy-n-paste error in `vtable_for` docs)

r? @ghost

Rollup of 10 pull requests

Successful merges:

 - #149976 (Add waker_fn and local_waker_fn to std::task)
 - #150074 (Update provider API docs)
 - #150094 (`c_variadic`: provide our own `va_arg` implementation for more targets)
 - #150164 (rustc: Fix `-Zexport-executable-symbols` on wasm)
 - #150569 (Ensure that static initializers are acyclic for NVPTX)
 - #150694 (./x check miri: enable check_only feature)
 - #150717 (Thread `--jobs` from `bootstrap` -> `compiletest` -> `run-make-support`)
 - #150736 (Add AtomicPtr::null)
 - #150787 (Add myself as co-maintainer for s390x-unknown-linux-musl)
 - #150789 (Fix copy-n-paste error in `vtable_for` docs)

r? @ghost

Rollup merge of #150694 - miri-check, r=clubby789,bjorn3

./x check miri: enable check_only feature

With this, we should no longer need to turn off the default features, so we can undo #149550.

@bjorn3 you seem to have a test setup to check if this works properly in terms of skipping all the work that should not be required -- could you test if this PR works as intended?

FWIW we could now remove `default_features` from `run_tool_check_step`. Not sure if that's worth it.