Fix mutable reborrow

Co-authored-by: bluss <bluss@users.noreply.github.com>

src/arrayvec.rs

@@ -504,7 +504,7 @@ impl<A: Array> ArrayVec<A> {
 
         while g.processed_len < original_len {
             let cur = unsafe { g.v.as_mut_ptr().add(g.processed_len) };
-            if !f(cur) {
+            if !f(&mut *cur) {
                 g.processed_len += 1;
                 g.deleted_cnt += 1;
                 unsafe { ptr::drop_in_place(cur) };