wpa_supplicant: add fix for CVE-2015-1863

Add upstream patch fixing CVE-2015-1863: buffer overflow of SSID buffer within
struct p2p_device that is allocated from heap.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>