Rollup merge of rust-lang#116019 - dtolnay:percratesearch, r=GuillaumeGomez

Delete obsolete `--disable-per-crate-search` rustdoc flag

This unstable flag is unused by rustdoc since rust-lang@ef96d57.

We should avoid landing this until after rust-lang/docs.rs#2225 is deployed to docs.rs.

Author: GuillaumeGomez

Diff for: src/librustdoc/lib.rs

@@ -503,13 +503,6 @@ fn opts() -> Vec<RustcOptGroup> {
                 "PATH",
             )
         }),
-        unstable("disable-per-crate-search", |o| {
-            o.optflagmulti(
-                "",
-                "disable-per-crate-search",
-                "disables generating the crate selector on the search box",
-            )
-        }),
         unstable("persist-doctests", |o| {
             o.optopt(
                 "",

Diff for: tests/run-make/issue-88756-default-output/output-default.stdout

@@ -133,9 +133,6 @@ Options:
                         Path string to force loading static files from in
                         output pages. If not set, uses combinations of '../'
                         to reach the documentation root.
-        --disable-per-crate-search 
-                        disables generating the crate selector on the search
-                        box
         --persist-doctests PATH
                         Directory to persist doctest executables into
         --show-coverage