Remove old/no longer used lower.rs

cranelift/isle/src/lower.rs

@@ -1,33 +0,0 @@
-use crate::ir::*;
-use crate::sema;
-
-struct LowerState<'a> {
-    tyenv: &'a sema::TypeEnv,
-    func: &'a sema::Func,
-    builder: FuncBuilder,
-    control_flow: ControlInput,
-}
-
-pub fn lower(tyenv: &sema::TypeEnv, func: &sema::Func) -> Func {
-    let mut builder = FuncBuilder::default();
-    let entry = builder.intern(Node::Entry);
-
-    let mut state = LowerState {
-        tyenv,
-        func,
-        builder,
-        control_flow: ControlInput(entry, 0),
-    };
-
-    if !func.is_extern && !func.is_inline {
-        for case in &func.cases {
-            state.lower_case(case);
-        }
-    }
-
-    state.builder.build()
-}
-
-impl<'a> LowerState<'a> {
-    fn lower_case(&mut self) {}
-}