rust: zerocopy: update to v0.8.52

Update our vendored copy of `zerocopy` (and `zerocopy-derive`) to v0.8.52.

Most SPDX identifiers have been added upstream at our request [1]
(without parentheses -- supporting them is an issue on the kernel side,
but it does already reduce our differences). The CSS one for `rustdoc`
was added too [2], but will be picked up in a later version.

For `zerocopy`, enable `--cfg no_fp_fmt_parse`, which was added at our
request to avoid our local workaround [3]. This means one less difference,
thus indicate so in our `README.md`.

For `zerocopy-derive`, enable `--cfg zerocopy_unstable_linux`. This
allows us to use `#[derive(zerocopy_derive::most_traits)]`, a new feature
upstream added for us [4]. We noticed a minor doc render bug [5], which
will be fixed for a future version too.

The following script may be used to check for the remaining differences:

    for path in $(cd rust/zerocopy-derive/ && find . -type f ! -name README.md); do
        curl --silent --show-error --location \
            https://github.com/google/zerocopy/raw/v0.8.52/zerocopy/zerocopy-derive/src/$path |
            git diff --no-index - rust/zerocopy-derive/$path &&
            echo $path: OK
    done

    for path in $(cd rust/zerocopy/ && find . -type f ! -name README.md); do
        curl --silent --show-error --location \
            https://github.com/google/zerocopy/raw/v0.8.52/zerocopy/$path |
            git diff --no-index - rust/zerocopy/$path &&
            echo $path: OK
    done

Cc: Joshua Liebow-Feeser <joshlf@google.com>
Cc: Jack Wrenn <jswrenn@google.com>
Link: https://github.com/google/zerocopy/issues/3428 [1]
Link: https://github.com/google/zerocopy/issues/3457 [2]
Link: https://github.com/google/zerocopy/issues/3426 [3]
Link: https://github.com/google/zerocopy/pull/3416 [4]
Link: https://github.com/google/zerocopy/issues/3466 [5]
Acked-by: Nicolas Schier <n.schier@fritz.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20260625231919.692444-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/rust/zerocopy/src/pointer/inner.rs b/rust/zerocopy/src/pointer/inner.rs
index 5db08080141f..949b60a3f83e 100644
--- a/rust/zerocopy/src/pointer/inner.rs
+++ b/rust/zerocopy/src/pointer/inner.rs
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: (BSD-2-Clause OR Apache-2.0) OR MIT
-
+//
 // Copyright 2024 The Fuchsia Authors
 //
 // Licensed under a BSD-style license <LICENSE-BSD>, Apache License, Version 2.0