actually fix line number

Author: pietroalbini

src/test/mir-opt/issue_101867.main.mir_map.0.mir

@@ -1,8 +1,8 @@
 // MIR for `main` 0 mir_map
 
 | User Type Annotations
-| 0: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(std::option::Option<u8>) }, span: $DIR/issue-101867.rs:3:12: 5:22, inferred_ty: std::option::Option<u8>
-| 1: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(std::option::Option<u8>) }, span: $DIR/issue-101867.rs:3:12: 5:22, inferred_ty: std::option::Option<u8>
+| 0: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(std::option::Option<u8>) }, span: $DIR/issue-101867.rs:3:12: 3:22, inferred_ty: std::option::Option<u8>
+| 1: user_ty: Canonical { max_universe: U0, variables: [], value: Ty(std::option::Option<u8>) }, span: $DIR/issue-101867.rs:3:12: 3:22, inferred_ty: std::option::Option<u8>
 |
 fn main() -> () {
     let mut _0: ();                      // return place in scope 0 at $DIR/issue-101867.rs:+0:11: +0:11