nilfs2: deletion of an unnecessary check before the function call "iput"

The iput() function tests whether its argument is NULL and then returns
immediately.  Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fs/nilfs2/the_nilfs.c

@@ -808,8 +808,7 @@ void nilfs_put_root(struct nilfs_root *root)
 		spin_lock(&nilfs->ns_cptree_lock);
 		rb_erase(&root->rb_node, &nilfs->ns_cptree);
 		spin_unlock(&nilfs->ns_cptree_lock);
-		if (root->ifile)
-			iput(root->ifile);
+		iput(root->ifile);
 
 		kfree(root);
 	}