Move qualify_min_const_fn out of rustc into clippy

clippy_lints/src/lib.rs

@@ -6,6 +6,7 @@
 #![feature(concat_idents)]
 #![feature(crate_visibility_modifier)]
 #![feature(drain_filter)]
+#![feature(in_band_lifetimes)]
 #![feature(or_patterns)]
 #![feature(rustc_private)]
 #![feature(stmt_expr_attributes)]

clippy_lints/src/missing_const_for_fn.rs

@@ -4,7 +4,7 @@ use rustc_hir::intravisit::FnKind;
 use rustc_hir::{Body, Constness, FnDecl, GenericParamKind, HirId};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::lint::in_external_macro;
-use rustc_mir::transform::qualify_min_const_fn::is_min_const_fn;
+use crate::utils::qualify_min_const_fn::is_min_const_fn;
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 use rustc_span::Span;
 use rustc_typeck::hir_ty_to_ty;

clippy_lints/src/utils/mod.rs

@@ -20,6 +20,7 @@ pub mod paths;
 pub mod ptr;
 pub mod sugg;
 pub mod usage;
+pub mod qualify_min_const_fn;
 
 pub use self::attrs::*;
 pub use self::diagnostics::*;