fix arm test

Author: estebank

Diff for: src/test/ui/asm/aarch64/type-check-2-2.rs

@@ -17,10 +17,10 @@ fn main() {
 
         let x: u64;
         asm!("{}", in(reg) x);
-        //~^ ERROR use of possibly-uninitialized variable: `x`
+        //~^ ERROR used binding `x` isn't initialized
         let mut y: u64;
         asm!("{}", inout(reg) y);
-        //~^ ERROR use of possibly-uninitialized variable: `y`
+        //~^ ERROR used binding `y` isn't initialized
         let _ = y;
 
         // Outputs require mutable places

Diff for: src/test/ui/asm/aarch64/type-check-2-2.stderr

@@ -1,14 +1,18 @@
-error[E0381]: use of possibly-uninitialized variable: `x`
+error[E0381]: used binding `x` isn't initialized
   --> $DIR/type-check-2-2.rs:19:28
    |
+LL |         let x: u64;
+   |             - binding declared here but left uninitialized
 LL |         asm!("{}", in(reg) x);
-   |                            ^ use of possibly-uninitialized `x`
+   |                            ^ `x` used here but it isn't initialized
 
-error[E0381]: use of possibly-uninitialized variable: `y`
+error[E0381]: used binding `y` isn't initialized
   --> $DIR/type-check-2-2.rs:22:9
    |
+LL |         let mut y: u64;
+   |             ----- binding declared here but left uninitialized
 LL |         asm!("{}", inout(reg) y);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^ use of possibly-uninitialized `y`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^ `y` used here but it isn't initialized
 
 error[E0596]: cannot borrow `v` as mutable, as it is not declared as mutable
   --> $DIR/type-check-2-2.rs:30:29