Pull Rust updates from Miguel Ojeda:
 "Another routine one in terms of features. We got two version upgrades
  this time, but in terms of lines, 'alloc' changes are not very large.

  Toolchain and infrastructure:

   - Upgrade to Rust 1.76.0

     This time around, due to how the kernel and Rust schedules have
     aligned, there are two upgrades in fact. These allow us to remove
     two more unstable features ('const_maybe_uninit_zeroed' and
     'ptr_metadata') from the list, among other improvements

   - Mark 'rustc' (and others) invocations as recursive, which fixes a
     new warning and prepares us for the future in case we eventually
     take advantage of the Make jobserver

  'kernel' crate:

   - Add the 'container_of!' macro

   - Stop using the unstable 'ptr_metadata' feature by employing the now
     stable 'byte_sub' method to implement 'Arc::from_raw()'

   - Add the 'time' module with a 'msecs_to_jiffies()' conversion
     function to begin with, to be used by Rust Binder

   - Add 'notify_sync()' and 'wait_interruptible_timeout()' methods to
     'CondVar', to be used by Rust Binder

   - Update integer types for 'CondVar'

   - Rename 'wait_list' field to 'wait_queue_head' in 'CondVar'

   - Implement 'Display' and 'Debug' for 'BStr'

   - Add the 'try_from_foreign()' method to the 'ForeignOwnable' trait

   - Add reexports for macros so that they can be used from the right
     module (in addition to the root)

   - A series of code documentation improvements, including adding
     intra-doc links, consistency improvements, typo fixes...

  'macros' crate:

   - Place generated 'init_module()' function in '.init.text'

  Documentation:

   - Add documentation on Rust doctests and how they work"

* tag 'rust-6.9' of https://github.com/Rust-for-Linux/linux: (29 commits)
  rust: upgrade to Rust 1.76.0
  kbuild: mark `rustc` (and others) invocations as recursive
  rust: add `container_of!` macro
  rust: str: implement `Display` and `Debug` for `BStr`
  rust: module: place generated init_module() function in .init.text
  rust: types: add `try_from_foreign()` method
  docs: rust: Add description of Rust documentation test as KUnit ones
  docs: rust: Move testing to a separate page
  rust: kernel: stop using ptr_metadata feature
  rust: kernel: add reexports for macros
  rust: locked_by: shorten doclink preview
  rust: kernel: remove unneeded doclink targets
  rust: kernel: add doclinks
  rust: kernel: add blank lines in front of code blocks
  rust: kernel: mark code fragments in docs with backticks
  rust: kernel: unify spelling of refcount in docs
  rust: str: move SAFETY comment in front of unsafe block
  rust: str: use `NUL` instead of 0 in doc comments
  rust: kernel: add srctree-relative doclinks
  rust: ioctl: end top-level module docs with full stop
  ...