Need some help, I want the fields "$srcip, $srcport, $dstip, $dstport" to be put together in another field, called "$netinfo", how do I do it ??

My logs

#fields    ts    uid    id.orig_h    id.orig_p    id.resp_h    id.resp_p    proto    trans_id    query    qclass    qclass_name    qtype    qtype_name    rcode    rcode_name    AA    TC    RD    RA    Z    answers    TTLs    rejected
#types    time    string    addr    port    addr    port    enum    count    string    count    string    count    string    count    string    bool    bool    bool    bool    count    vector[string]    vector[interval]    bool
1482865188.959602    CMyjvLxxxxxxx0MJjb    xxx.xx.192.250    3xxx    xxx.xxx.162.xxx    53    udp    19626    -    -    -    -    -    0    NOERROR    F    F    F    F    0    -    -    F
1482865189.162798    CW1kwxxxxxxxC3Ug0j    xxx.xx.192.250    xxxx5    xxx.xxx.xxx.xxx    53    udp    250    r4.sn-a5m7znes.googlevideo.com    -    -    -    -    0    NOERROR    T    F    F    F    0    xxx.194.xxx.233    1800.000000    F
1482865189.182565    Cir6Sz3xxxxxO60PD6    fe80::xxx:f35c:xxxx:61ad    65535    ff02::1:3    5355    udp    1772    host    1    C_INTERNET    1    A    -    -    F    F    F    F    0    -    -    F

Nxlog .conf
<Extension csv.dns.log>
 Module xm_csv
 Fields $timestamp,$uid,$srcip,$srcport,$dstip,$dstport,$service,$transid,$qresponse,$query,$qclass,$qclassname,$qtype,$qtypename,$rcode,$rcodename,$aa,$tc,$rd,$ra,$z,$answ
 FieldsType string,string,string,string,string,string,string,string,string,string,string,string,string,string,string,string,string,string,string,string,string,string,string
 Delimiter \t
</Extension>
<Input i.dns.log>
 Module im_file
 File "/*PATH*/dns.log"
 ReadFromLast TRUE
 Exec csv.dns.log->parse_csv();
</Input>
<Output o.dns.log>
 Module om_ssl
 Host 192.XXX.X.XXX
 Port ZZZZ
 OutputType GELF_TCP
 CAFile /data/conf/ca.crt
 AllowUntrusted TRUE
</Output>
<Route r.dns.log>
 Path i.dns.log => o.dns.log
</Route>

Thank you