freediameter: Fix testcnx ptest failure

Currently, testcnx ptest fails due to expired CA certificates:
Test project /usr/lib64/freeDiameter/ptest
...
Start 10: testcnx
10/11 Test #10: testcnx ..........................***Failed 0.12 sec
...

<snip>
Command: "/usr/lib64/freeDiameter/ptest/testcnx"
Directory: /usr/lib64/freeDiameter/ptest
"testcnx" start time: Jun 17 10:52 UTC
Output:
----------------------------------------------------------
10:52:43  ERROR  ERROR: Invalid parameter '(conn->cc_rcvthr != (pthread_t)((voidd
 *)0))', 22
10:52:43  ERROR  TLS: Remote certificate invalid on socket 6 (Remote: 'localhostt
.localdomain')(Connection: '{---T} TCP from [127.0.0.1]:57898 (4<-6)') :
10:52:43  ERROR   - The certificate has expired.
10:52:43  ERROR  TLS ERROR: in 'ret = gnutls_handshake(conn->cc_tls_para.sessionn
)' :    Error in the certificate.
10:52:43  FATAL! testcnx.c:867: CHECK FAILED : fd_cnx_handshake(server_side, GNUU
TLS_SERVER, ALGO_HANDSHAKE_DEFAULT , NULL, NULL) == 16 != 0
10:52:43  FATAL! FAILED: testcnx.c
<end of output>
Test time =   0.02 sec
<snip>

Backport upstream patch [1] to fix this issue.

[1] http://www.freediameter.net/hg/freeDiameter/rev/eff5bb332b5a

This patch is present in version 1.4.0, so master is not affected.

Signed-off-by: Ovidiu Panait <[email protected]>

Signed-off-by: Armin Kuster <[email protected]>