FUNCTION SPH_R3_LOGOFF.
*"----------------------------------------------------------------------
*"*"Lokale Schnittstelle:
*"----------------------------------------------------------------------
* This function module should be called in the R/3 logoff procedure.
* It deleletes the assignment of the current user to the current
* terminal in the SAPphone table SPH_TERMNL. The terminal-ID is
* retrieved from the workcenter-PC (e.g. registry). If there is an
* an entry for this terminal in the table, the assignment of user to
* terminal is deleted.
* If there is no entry in the table, nothing happens.
* If there is no ID stored on the PC, nothing happens.
* If telephony is switched off clientwide, nothing happens.