docs: rust: link to https://rust.docs.kernel.org

The Rust code documentation (i.e. `rustdoc`-generated docs) is now
available at:

    https://rust.docs.kernel.org

Thus document it and remove the `TODO` line.

The generation uses a particular kernel configuration, based on x86_64,
which may get tweaked over time. Older tags, and how they are generated,
may also change in the future. We may consider freezing them at some
point, but for the moment, the content should not be considered immutable.

Thanks Konstantin for the support setting it up!

Cc: Konstantin Ryabitsev <konstantin@linuxfoundation.org>
Acked-by: Konstantin Ryabitsev <konstantin@linuxfoundation.org>
Link: https://lore.kernel.org/r/20240818141200.386899-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Documentation/rust/general-information.rst

@@ -22,10 +22,17 @@ Rust kernel code is documented using ``rustdoc``, its built-in documentation
 generator.
 
 The generated HTML docs include integrated search, linked items (e.g. types,
-functions, constants), source code, etc. They may be read at (TODO: link when
-in mainline and generated alongside the rest of the documentation):
+functions, constants), source code, etc. They may be read at:
 
-	http://kernel.org/
+	https://rust.docs.kernel.org
+
+For linux-next, please see:
+
+	https://rust.docs.kernel.org/next/
+
+There are also tags for each main release, e.g.:
+
+	https://rust.docs.kernel.org/6.10/
 
 The docs can also be easily generated and read locally. This is quite fast
 (same order as compiling the code itself) and no special tools or environment

Documentation/rust/index.rst

@@ -32,6 +32,9 @@ configurations.
 .. only:: not rustdoc and html
 
 	This documentation does not include rustdoc generated information.
+	A pregenerated version is provided at:
+
+		https://rust.docs.kernel.org
 
 .. toctree::
     :maxdepth: 1