core: Remove some redundant {}s from the sorting code

Author: est31

library/core/src/slice/sort.rs

@@ -773,7 +773,7 @@ where
                 let mid = partition_equal(v, pivot, is_less);
 
                 // Continue sorting elements greater than the pivot.
-                v = &mut { v }[mid..];
+                v = &mut v[mid..];
                 continue;
             }
         }
@@ -784,7 +784,7 @@ where
         was_partitioned = was_p;
 
         // Split the slice into `left`, `pivot`, and `right`.
-        let (left, right) = { v }.split_at_mut(mid);
+        let (left, right) = v.split_at_mut(mid);
         let (pivot, right) = right.split_at_mut(1);
         let pivot = &pivot[0];
 
@@ -860,7 +860,7 @@ fn partition_at_index_loop<'a, T, F>(
         let (mid, _) = partition(v, pivot, is_less);
 
         // Split the slice into `left`, `pivot`, and `right`.
-        let (left, right) = { v }.split_at_mut(mid);
+        let (left, right) = v.split_at_mut(mid);
         let (pivot, right) = right.split_at_mut(1);
         let pivot = &pivot[0];