rustc: Fix crate lint for single-item paths

This commit fixes recommending the `crate` prefix when migrating to 2018 for
paths that look like `use foo;` or `use {bar, baz}`

Closes #50660

src/librustc/lint/builtin.rs

@@ -261,7 +261,7 @@ declare_lint! {
 }
 
 declare_lint! {
-    pub ABSOLUTE_PATH_STARTING_WITH_MODULE,
+    pub ABSOLUTE_PATH_NOT_STARTING_WITH_CRATE,
     Allow,
     "fully qualified paths that start with a module name \
      instead of `crate`, `self`, or an extern crate name"
@@ -328,7 +328,7 @@ impl LintPass for HardwiredLints {
             TYVAR_BEHIND_RAW_POINTER,
             ELIDED_LIFETIME_IN_PATH,
             BARE_TRAIT_OBJECT,
-            ABSOLUTE_PATH_STARTING_WITH_MODULE,
+            ABSOLUTE_PATH_NOT_STARTING_WITH_CRATE,
             UNSTABLE_NAME_COLLISION,
         )
     }