[#2176] Replace sfl.zid in .cache/sflphone instead of .sflphone

sflphone-common/src/audio/audiortp/AudioZrtpSession.cpp

@@ -47,7 +47,10 @@ namespace sfl {
             throw ZrtpZidException();
         }
 
-        std::string zidCompleteFilename = std::string(HOMEDIR) + DIR_SEPARATOR_STR + "." + PROGDIR + "/" + _zidFilename;
+        std::string zidCompleteFilename = std::string(HOMEDIR) + DIR_SEPARATOR_STR + ".cache" + DIR_SEPARATOR_STR + PROGDIR + "/" + _zidFilename;
+        
+	_debug("Initialize Zid: try to find zid in: %s\n", zidCompleteFilename.c_str());
+
 
         if(initialize(zidCompleteFilename.c_str()) >= 0) {
             _debug("Register callbacks\n");