USN-4734-2: wpa_supplicant and hostapd vulnerabilities

USN-4734-1 fixed several vulnerabilities in wpa_supplicant. This
update provides the corresponding update for Ubuntu 14.04 ESM.

It was discovered that wpa_supplicant did not properly handle P2P
(Wi-Fi Direct) group information in some situations, leading to a
heap overflow. A physically proximate attacker could use this to cause a
denial of service or possibly execute arbitrary code. (CVE-2021-0326)

It was discovered that hostapd did not properly handle UPnP subscribe
messages in some circumstances. An attacker could use this to cause a
denial of service. (CVE-2020-12695)