openssl: security bump to version 1.0.2b

CVE-2015-1790 - PKCS7 crash with missing EnvelopedContent
CVE-2015-1789 - Exploitable out-of-bounds read in X509_cmp_time
CVE-2015-1788 - Malformed ECParameters causes infinite loop
CVE-2015-1792 - CMS verify infinite loop with unknown hash function
CVE-2015-1791 - Race condition handling NewSessionTicket

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>