package/haproxy: security bump to version 2.4.4

package/haproxy: security bump to version 2.4.4

Fixes the following security issues:

- CVE-2021-40346: An integer overflow exists in HAProxy 2.0 through 2.5 in
  the htx_add_header() can be exploited to perform an HTTP request smuggling
  attack, allowing an attacker to bypass all configured http-request HAProxy
  ACLs and possibly other ACLs.

For more details, see the advisory:
https://www.mail-archive.com/haproxy@formilux.org/msg41114.html

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>