Remove Licensing exchange

[matt335672]

Fixes #3132

Replaces the existing licensing exchange with a single PDU saying the server will not issue a license.

This is necessary for clients on FIPS-compliant systems, as these are unable to decode the licensing exchange PDUs, due to outdated cyphers in the licensing PDUs.

As far as FIPS mode goes, this is tested with xfreerdp 2.11.2 on Alma 9 in FIPS mode connecting to Ubuntu with fips configured in /etc/xrdp/xrdp.ini. Command is xfreerdp +fipsmode /v:<host>. The /etc/xrdp/xrdp.ini config is actually irrelevant as in any case the connection needs to take place over TLS because of #2266.

Without this change the connection fails with:-

[14:31:38:701] [3394:3395] [DEBUG][com.freerdp.core.connection] - rdp_client_transition_to_state CONNECTION_STATE_MCS_CHANNEL_JOIN --> CONNECTION_STATE_LICENSING
[14:31:39:801] [3394:3395] [DEBUG][com.freerdp.core.rdp] - rdp_recv_callback: CONNECTION_STATE_LICENSING - rdp_client_connect_license() - -1
[14:31:39:802] [3394:3395] [DEBUG][com.freerdp.core.rdp] - transport_check_fds() - -1

@akallabeth - With FreeRDP 3.5.1 I'm getting the following warning sending an empty BLOB in the license error PDU:-

[14:34:02:508] [50170:0000c3fb] [WARN][com.freerdp.core.license] - [license_read_binary_blob_data]: license binary blob::type BB_ERROR_BLOB, length=0, skipping.

Revised code is now here:-

    /* [MS-RDPBCGR] TS_SECURITY_HEADER */
    /* A careful reading of [MS-RDPBCGR] 2.2.1.12 shows that a securityHeader
     * MUST be included, and provided the flag fields of the header does
     * not contain SEC_ENCRYPT, it is always possible to send a basic
     * security header */
    out_uint16_le(s, SEC_LICENSE_PKT | SEC_LICENSE_ENCRYPT_CS); /* flags */
    out_uint16_le(s, 0); /* flagsHi */

    /* [MS-RDPBCGR] LICENSE_VALID_CLIENT_DATA */
    /* preamble (LICENSE_PREAMBLE) */
    out_uint8(s, ERROR_ALERT);
    out_uint8(s, PREAMBLE_VERSION_3_0);
    out_uint16_le(s, 16); /* Message size, including pre-amble */

    /* validClientMessage */
    /* From [MS-RDPBCGR] 2.2.12.1, dwStateTransition must be ST_NO_TRANSITION,
     * and the bbErrorInfo field must contain an empty blob of type
     * BB_ERROR_BLOB */
    out_uint32_le(s, STATUS_VALID_CLIENT); /* dwErrorCode */
    out_uint32_le(s, ST_NO_TRANSITION); /* dwStateTransition */
    out_uint16_le(s, BB_ERROR_BLOB);    /* wBlobType */
    out_uint16_le(s, 0);                /* wBlobLen */
    s_mark_end(s);

I'm pretty sure I'm standards-compliant with this, but I've been wrong about that before. I'd appreciate your comment on that.

[jsorg71]

LGTM