Update error annotations in tests that successfully compile

Those annotation are silently ignored rather than begin validated
against compiler output. Update them before validation is enabled,
to avoid test failures.

Author: tmiasko

src/test/ui/conditional-compilation/cfg-attr-multi-true.rs

@@ -17,5 +17,5 @@ impl MustUseDeprecated { //~ warning: use of deprecated item
 
 fn main() {
     MustUseDeprecated::new(); //~ warning: use of deprecated item
-    //| warning: unused `MustUseDeprecated` that must be used
+    //~| warning: unused `MustUseDeprecated` that must be used
 }

src/test/ui/const-generics/cannot-infer-type-for-const-param.rs

@@ -8,6 +8,5 @@
 struct Foo<const NUM_BYTES: usize>(pub [u8; NUM_BYTES]);
 
 fn main() {
-    let _ = Foo::<3>([1, 2, 3]); //~ ERROR type annotations needed
-    //~^ ERROR mismatched types
+    let _ = Foo::<3>([1, 2, 3]);
 }

src/test/ui/const-generics/issues/issue-62187-encountered-polymorphic-const.rs

@@ -12,5 +12,5 @@ impl<const L: usize> BitLen for [u8; L] {
 }
 
 fn main() {
-    let foo = <[u8; 2]>::BIT_LEN;
+    let foo = <[u8; 2]>::BIT_LEN; //~ WARN unused variable
 }

src/test/ui/derive-uninhabited-enum-38885.rs

@@ -10,7 +10,7 @@ enum Void {}
 #[derive(Debug)]
 enum Foo {
     Bar(u8),
-    Void(Void), //~ WARN never used
+    Void(Void), //~ WARN never constructed
 }
 
 fn main() {

src/test/ui/feature-gate/issue-43106-gating-of-builtin-attrs.rs

@@ -38,6 +38,7 @@
 // Exception, a gated and deprecated attribute.
 
 #![plugin_registrar] //~ WARN unused attribute
+//~| WARN use of deprecated attribute
 
 // UNGATED WHITE-LISTED BUILT-IN ATTRIBUTES
 
@@ -90,7 +91,7 @@
 #![crate_id = "10"] //~ WARN use of deprecated attribute
 
 // FIXME(#44232) we should warn that this isn't used.
-#![feature(rust1)]
+#![feature(rust1)] //~ WARN no longer requires an attribute to enable
 
 #![no_start] //~ WARN use of deprecated attribute
 
@@ -215,20 +216,25 @@ mod macro_export {
 
 #[plugin_registrar]
 //~^ WARN unused attribute
+//~| WARN use of deprecated attribute
 mod plugin_registrar {
     mod inner { #![plugin_registrar] }
     //~^ WARN unused attribute
+    //~| WARN use of deprecated attribute
 
     // for `fn f()` case, see gated-plugin_registrar.rs
 
     #[plugin_registrar] struct S;
     //~^ WARN unused attribute
+    //~| WARN use of deprecated attribute
 
     #[plugin_registrar] type T = S;
     //~^ WARN unused attribute
+    //~| WARN use of deprecated attribute
 
     #[plugin_registrar] impl S { }
     //~^ WARN unused attribute
+    //~| WARN use of deprecated attribute
 }
 
 #[main]