ext4: update ctime when changing the file's permission by setfacl

ext4 didn't update the ctime of the file when its permission was
changed.

Steps to reproduce:
 # touch aaa
 # stat -c %Z aaa
 1275289822
 # setfacl -m  'u::x,g::x,o::x' aaa
 # stat -c %Z aaa
 1275289822                         <- unchanged

But, according to the spec of the ctime, ext4 must update it.

Port of ext3 patch by Miao Xie <miaox@cn.fujitsu.com>.

CC: linux-ext4@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

fs/ext4/acl.c

@@ -204,6 +204,7 @@ ext4_set_acl(handle_t *handle, struct inode *inode, int type,
 				return error;
 			else {
 				inode->i_mode = mode;
+				inode->i_ctime = ext4_current_time(inode);
 				ext4_mark_inode_dirty(handle, inode);
 				if (error == 0)
 					acl = NULL;