Rollup merge of rust-lang#94122 - GuillaumeGomez:miniz-oxide-std, r=notriddle

Fix miniz_oxide types showing up in std docs

Fixes rust-lang#90526.

Thanks to ```````@camelid,``````` I rediscovered `doc(masked)`, allowing us to prevent `miniz_oxide` type to show up in std docs.

r? ```````@notriddle```````

Author: matthiaskrgr

library/std/src/lib.rs

@@ -364,6 +364,10 @@ extern crate libc;
 #[allow(unused_extern_crates)]
 extern crate unwind;
 
+#[doc(masked)]
+#[allow(unused_extern_crates)]
+extern crate miniz_oxide;
+
 // During testing, this crate is not actually the "real" std library, but rather
 // it links to the real std library, which was compiled from this same source
 // code. So any lang items std defines are conditionally excluded (or else they