malloc: remove redundant check of unsorted bin corruption

malloc: remove redundant check of unsorted bin corruption

* malloc/malloc.c (_int_malloc): remove redundant check of
  unsorted bin corruption

With commit "b90ddd08f6dd688e651df9ee89ca3a69ff88cd0c"
(malloc: Additional checks for unsorted bin integrity),
same check of (bck->fd != victim) is added before checking of unsorted
chunk corruption, which was added in "bdc3009b8ff0effdbbfb05eb6b10966753cbf9b8"
(Added check before removing from unsorted list).

..
3773           if (__glibc_unlikely (bck->fd != victim)
3774               || __glibc_unlikely (victim->fd != unsorted_chunks (av)))
3775             malloc_printerr ("malloc(): unsorted double linked list corrupted");
..
..
3815           /* remove from unsorted list */
3816          if (__glibc_unlikely (bck->fd != victim))
3817            malloc_printerr ("malloc(): corrupted unsorted chunks 3");
3818          unsorted_chunks (av)->bk = bck;
..

So this extra check can be removed.

Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
Signed-off-by: Ayush Mittal <ayush.m@samsung.com>
Reviewed-by: DJ Delorie <dj@redhat.com>