cifs: Fix smb311_update_preauth_hash() kernel-doc comment

Add the description of @server in smb311_update_preauth_hash()
kernel-doc comment to remove warning found by running scripts/kernel-doc,
which is caused by using 'make W=1'.
fs/cifs/smb2misc.c:856: warning: Function parameter or member 'server'
not described in 'smb311_update_preauth_hash'

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

fs/cifs/smb2misc.c

@@ -847,6 +847,7 @@ smb2_handle_cancelled_mid(struct mid_q_entry *mid, struct TCP_Server_Info *serve
  * SMB2 header.
  *
  * @ses:	server session structure
+ * @server:	pointer to server info
  * @iov:	array containing the SMB request we will send to the server
  * @nvec:	number of array entries for the iov
  */