SUMMARY: rename rustdoc links into "Rust code documentation"

Signed-off-by: Miguel Ojeda <[email protected]>

Author: ojeda

SUMMARY.md

@@ -59,8 +59,8 @@
 
   - [Kernel documentation (mainline)](https://docs.kernel.org/rust/)
   - [Kernel documentation (next)](https://docs.kernel.org/next/rust/)
-  - [`rustdoc` code docs (v6.8)](https://rust-for-linux.github.io/docs/v6.8/kernel/)
-  - [`rustdoc` code docs (`rust` 2023-03-13)](https://rust-for-linux.github.io/docs/rust/kernel/)
+  - [Rust code documentation (v6.8)](https://rust-for-linux.github.io/docs/v6.8/kernel/)
+  - [Rust code documentation (`rust` 2023-03-13)](https://rust-for-linux.github.io/docs/rust/kernel/)
   - [Out-of-tree module template](https://github.com/Rust-for-Linux/rust-out-of-tree-module)
 
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