don't bother with ->d_inode->i_sb - it's always equal to ->d_sb

... and neither can ever be NULL

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/jffs2/super.c b/fs/jffs2/super.c
index 0a9a114..5ef21f4 100644
--- a/fs/jffs2/super.c
+++ b/fs/jffs2/super.c
@@ -147,7 +147,7 @@
 	JFFS2_DEBUG("Parent of directory ino #%u is #%u\n",
 		    f->inocache->ino, pino);
 
-	return d_obtain_alias(jffs2_iget(d_inode(child)->i_sb, pino));
+	return d_obtain_alias(jffs2_iget(child->d_sb, pino));
 }
 
 static const struct export_operations jffs2_export_ops = {