chore(tvix/eval): Pass in VM to nix_eq

Pass in, but ignore, a mutable reference to the VM to the `nix_eq`
functions, in preparation for using that VM to force thunks during
comparison.

Change-Id: I565435d8dfb33768f930fdb5a6b0fb1365d7e161
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6651
Autosubmit: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Reviewed-by: tazjin <tazjin@tvl.su>

tvix/eval/src/value/list.rs

@@ -2,6 +2,7 @@
 use std::fmt::Display;
 
 use crate::errors::ErrorKind;
+use crate::vm::VM;
 
 use super::Value;
 
@@ -83,13 +84,13 @@ impl NixList {
     }
 
     /// Compare `self` against `other` for equality using Nix equality semantics
-    pub fn nix_eq(&self, other: &Self) -> Result<bool, ErrorKind> {
+    pub fn nix_eq(&self, other: &Self, vm: &mut VM) -> Result<bool, ErrorKind> {
         if self.len() != other.len() {
             return Ok(false);
         }
 
         for (v1, v2) in self.iter().zip(other.iter()) {
-            if !v1.nix_eq(v2)? {
+            if !v1.nix_eq(v2, vm)? {
                 return Ok(false);
             }
         }