ext4: remove unmeetable inconsisteny check from ext4_find_extent()

ext4_find_extent(), stripped down to the parts relevant to this patch,
reads as

  ppos = 0;
  i = depth;
  while (i) {
    --i;
    ++ppos;
    if (unlikely(ppos > depth)) {
      ...
      ret = -EFSCORRUPTED;
      goto err;
    }
  }

Due to the loop's bounds, the condition ppos > depth can never be met.

Remove this dead code.
Signed-off-by: NNicolai Stange <nicstange@gmail.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

fs/ext4/extents.c

@@ -912,13 +912,6 @@ ext4_find_extent(struct inode *inode, ext4_lblk_t block,
 
 		eh = ext_block_hdr(bh);
 		ppos++;
-		if (unlikely(ppos > depth)) {
-			put_bh(bh);
-			EXT4_ERROR_INODE(inode,
-					 "ppos %d > depth %d", ppos, depth);
-			ret = -EFSCORRUPTED;
-			goto err;
-		}
 		path[ppos].p_bh = bh;
 		path[ppos].p_hdr = eh;
 	}