add: DBG("DEBUG: sip_msg_free : cseq headers\n");
context: void clean_hdr_field(struct hdr_field* hf){   if (hf->parsed)   {      switch(hf->type)      {         case HDR_VIA:               free_via_list(hf->parsed);             break;         case HDR_CSEQ:                sh_free(hf->parsed);             break;         default:      }   }}