Bug 1449605

Description of problem:
This patch (http://pkgs.fedoraproject.org/cgit/rpms/libvncserver.git/tree/LibVNCServer-0.9.10-system-crypto-policy.patch) changes the TLS priority string but it leaves in +SRP which is not supported by Fedora's version of GnuTLS.  GnuTLS rejects the priority string and the connection fails.

Version-Release number of selected component (if applicable):
0.9.10, 0.9.11

How reproducible:
Always.

Steps to Reproduce:
1. Start a TigerVNCServer with x509vnc enabled
2. Try to connect using Remmina as client (which uses libvncserver's client)

Actual results:
Remmina fails with an authentication failed error, but looking through the debug output of Remmina and GnuTLS shows that the priority string is wrong:

Remmina:

[VNC]VNC server supports protocol version 3.8 (viewer 3.8)
[VNC]We have 1 security types to read
[VNC]0) Received security type 19
[VNC]Selecting security type 19 (0/1 in the list)
[VNC]Selected Security Scheme 19
[VNC]GnuTLS initialized.
[VNC]Got VeNCrypt version 0.2 from server.
[VNC]We have 1 security types to read
[VNC]0) Received security type 261
[VNC]Selecting security type 261 (0/1 in the list)
[VNC]No client certificate or key provided.
[VNC]No CRL provided.
[VNC]TLS session initialized.
[VNC]TLS handshake failed: No or insufficient priorities were set..

GNUTLS_DEBUG_LEVEL=99:
gnutls[3]: ASSERT: extensions.c[_gnutls_get_extension]:65
gnutls[3]: ASSERT: extensions.c[_gnutls_get_extension]:65
gnutls[3]: ASSERT: mpi.c[_gnutls_x509_read_uint]:246
gnutls[5]: REC[0x7fc83805c530]: Allocating epoch #0
gnutls[2]: system priority /etc/crypto-policies/back-ends/gnutls.config has not changed
gnutls[2]: resolved 'SYSTEM' to 'NONE:+AEAD:+SHA1:+SHA256:+SHA384:+SHA512:+CURVE-SECP256R1:+CURVE-SECP384R1:+CURVE-SECP521R1:+SIGN-ALL:-SIGN-RSA-MD5:+AES-256-GCM:+AES-256-CCM:+CHACHA20-POLY1305:+CAMELLIA-256-GCM:+AES-256-CBC:+CAMELLIA-256-CBC:+AES-128-GCM:+AES-128-CCM:+CAMELLIA-128-GCM:+AES-128-CBC:+CAMELLIA-128-CBC:+3DES-CBC:+ECDHE-RSA:+ECDHE-ECDSA:+RSA:+DHE-RSA:+DHE-DSS:+PSK:+DHE-PSK:+ECDHE-PSK:+VERS-TLS1.2:+VERS-TLS1.1:+VERS-TLS1.0:+VERS-DTLS1.2:+VERS-DTLS1.0:+COMP-NULL:%PROFILE_LOW', next ''
gnutls[2]: selected priority string: NONE:+AEAD:+SHA1:+SHA256:+SHA384:+SHA512:+CURVE-SECP256R1:+CURVE-SECP384R1:+CURVE-SECP521R1:+SIGN-ALL:-SIGN-RSA-MD5:+AES-256-GCM:+AES-256-CCM:+CHACHA20-POLY1305:+CAMELLIA-256-GCM:+AES-256-CBC:+CAMELLIA-256-CBC:+AES-128-GCM:+AES-128-CCM:+CAMELLIA-128-GCM:+AES-128-CBC:+CAMELLIA-128-CBC:+3DES-CBC:+ECDHE-RSA:+ECDHE-ECDSA:+RSA:+DHE-RSA:+DHE-DSS:+PSK:+DHE-PSK:+ECDHE-PSK:+VERS-TLS1.2:+VERS-TLS1.1:+VERS-TLS1.0:+VERS-DTLS1.2:+VERS-DTLS1.0:+COMP-NULL:%PROFILE_LOW:+SRP
gnutls[3]: ASSERT: priority.c[gnutls_priority_set_direct]:1497
gnutls[3]: ASSERT: handshake.c[gnutls_handshake]:2577
gnutls[5]: REC[0x7fc83805c530]: Start of epoch cleanup
gnutls[5]: REC[0x7fc83805c530]: End of epoch cleanup
gnutls[5]: REC[0x7fc83805c530]: Epoch #0 freed

Expected results:
Remmina should connect successfully.

Additional info: