kernel/kallsyms.c: use __seq_open_private()

Reduce boilerplate code by using __seq_open_private() instead of
seq_open() in kallsyms_open().

Signed-off-by: Rob Jones <rob.jones@codethink.co.uk>
Cc: Gideon Israel Dsouza <gidisrael@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/kallsyms.c

@@ -565,19 +565,12 @@ static int kallsyms_open(struct inode *inode, struct file *file)
 	 * using get_symbol_offset for every symbol.
 	 */
 	struct kallsym_iter *iter;
-	int ret;
-
-	iter = kmalloc(sizeof(*iter), GFP_KERNEL);
+	iter = __seq_open_private(file, &kallsyms_op, sizeof(*iter));
 	if (!iter)
 		return -ENOMEM;
 	reset_iter(iter, 0);
 
-	ret = seq_open(file, &kallsyms_op);
-	if (ret == 0)
-		((struct seq_file *)file->private_data)->private = iter;
-	else
-		kfree(iter);
-	return ret;
+	return 0;
 }
 
 #ifdef	CONFIG_KGDB_KDB