smb3: fix touch -h of symlink

For example:
      touch -h -t 02011200 testfile
where testfile is a symlink would not change the timestamp, but
      touch -t 02011200 testfile
does work to change the timestamp of the target

Suggested-by: David Howells <dhowells@redhat.com>
Reported-by: Micah Veilleux <micah.veilleux@iba-group.com>
Closes: https://bugzilla.samba.org/show_bug.cgi?id=14476
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>

Author: smfrench

fs/smb/client/cifsfs.c

@@ -1191,6 +1191,7 @@ const char *cifs_get_link(struct dentry *dentry, struct inode *inode,
 
 const struct inode_operations cifs_symlink_inode_ops = {
 	.get_link = cifs_get_link,
+	.setattr = cifs_setattr,
 	.permission = cifs_permission,
 	.listxattr = cifs_listxattr,
 };