Rollup merge of #122373 - surechen:fix_121331, r=petrochenkov

Fix the conflict problem between the diagnostics fixes of lint `unnecessary_qualification`  and  `unused_imports`

fixes #121331

For an `item` that triggers lint unnecessary_qualification, if the `use item` which imports this item is also trigger unused import, fixing the two lints at the same time may lead to the problem that the `item` cannot be found.
This PR will avoid reporting lint unnecessary_qualification when conflict occurs.

r? ``@petrochenkov``

compiler/rustc_lint_defs/src/builtin.rs

@@ -557,6 +557,7 @@ declare_lint! {
     /// fn main() {
     ///     use foo::bar;
     ///     foo::bar();
+    ///     bar();
     /// }
     /// ```
     ///