remove unused features from some tests

Author: WaffleLapkin

tests/ui/lint/unused/issue-103320-must-use-ops.rs

@@ -1,7 +1,6 @@
 //@ check-pass
 
 #![warn(unused_must_use)]
-#![feature(never_type)]
 
 use std::ops::Add;
 use std::ops::Sub;

tests/ui/lint/unused/issue-103320-must-use-ops.stderr

@@ -1,5 +1,5 @@
 warning: unused return value of `add` that must be used
-  --> $DIR/issue-103320-must-use-ops.rs:16:5
+  --> $DIR/issue-103320-must-use-ops.rs:15:5
    |
 LL |     x.add(4);
    |     ^^^^^^^^
@@ -16,7 +16,7 @@ LL |     let _ = x.add(4);
    |     +++++++
 
 warning: unused return value of `sub` that must be used
-  --> $DIR/issue-103320-must-use-ops.rs:18:5
+  --> $DIR/issue-103320-must-use-ops.rs:17:5
    |
 LL |     x.sub(4);
    |     ^^^^^^^^
@@ -28,7 +28,7 @@ LL |     let _ = x.sub(4);
    |     +++++++
 
 warning: unused return value of `mul` that must be used
-  --> $DIR/issue-103320-must-use-ops.rs:20:5
+  --> $DIR/issue-103320-must-use-ops.rs:19:5
    |
 LL |     x.mul(4);
    |     ^^^^^^^^
@@ -40,7 +40,7 @@ LL |     let _ = x.mul(4);
    |     +++++++
 
 warning: unused return value of `div` that must be used
-  --> $DIR/issue-103320-must-use-ops.rs:22:5
+  --> $DIR/issue-103320-must-use-ops.rs:21:5
    |
 LL |     x.div(4);
    |     ^^^^^^^^
@@ -52,7 +52,7 @@ LL |     let _ = x.div(4);
    |     +++++++
 
 warning: unused return value of `rem` that must be used
-  --> $DIR/issue-103320-must-use-ops.rs:24:5
+  --> $DIR/issue-103320-must-use-ops.rs:23:5
    |
 LL |     x.rem(4);
    |     ^^^^^^^^

tests/ui/never_type/auto-traits.rs

@@ -1,7 +1,6 @@
 //@ check-pass
 
 #![feature(auto_traits)]
-#![feature(negative_impls)]
 #![feature(never_type)]
 
 fn main() {

tests/ui/process/process-panic-after-fork.rs

@@ -8,7 +8,6 @@
 //@ ignore-backends: gcc
 
 #![feature(rustc_private)]
-#![feature(never_type)]
 #![feature(panic_always_abort)]
 
 #![allow(invalid_from_utf8)]