### Description

Kamailio v5.5.6 with topos module and postgres DB.

UAC (A) -> Kamailio Registrar (B) -> Kamailio PSTN GW (C) -> PSTN (D) Call goes from A to D, PSTN sends UPDATE, UPDATE is routed from C to A instead to B and then to A.

#### Reproduction

Caller calls callee and receives an UPDATE from callee. In my case it was when the call was routed to voicemail.

#### Log Messages

``` Kamailio takes the wrong route in UPDATE (upstream) case.

May 3 15:23:12 sipproxy /usr/sbin/kamailio[263013]: DEBUG: topos [tps_msg.c:882]: tps_request_received(): r-uri updated to: [sip:1234@<UAC-IP>;uniq=B0EB9A84A278626DA07219E2AE01C] May 3 15:23:12 sipproxy /usr/sbin/kamailio[263013]: DEBUG: topos [tps_msg.c:187]: tps_add_headers(): adding to headers(0) - [Route: sip:<<KamailioPSTNgwIP>>;lr=on;ftag=9945501E2B94B883;did=1fc.42f;nat=yes#015#012] May 3 15:23:12 sipproxy /usr/sbin/kamailio[263013]: DEBUG: topos [tps_msg.c:187]: tps_add_headers(): adding to headers(0) - [P-SR-XUID: atpsh-64527b0a-40362-1#015#012]

The right one would be the x_rr (a_rr), but it takes only the s_rr:

May 3 15:23:12 sipproxy /usr/sbin/kamailio[263013]: DEBUG: db_postgres [km_res.c:234]: db_postgres_convert_rows(): PQgetvalue(0x7fcb4893db50,0,7)=[sip:<KamailioRegistrarIP>;lr=on;ftag=9945501E2B94B883;did=1fc.7b92] May 3 15:23:12 sipproxy /usr/sbin/kamailio[263013]: DEBUG: db_postgres [km_res.c:242]: db_postgres_convert_rows(): [0][7] Column[x_rr]=[sip:<KamailioRegistrarIP>;lr=on;ftag=9945501E2B94B883;did=1fc.7b92]

May 3 15:23:12 sipproxy /usr/sbin/kamailio[263013]: DEBUG: db_postgres [km_res.c:234]: db_postgres_convert_rows(): PQgetvalue(0x7fcb4893db50,0,8)=[sip:<PSTNgw>:5060;transport=udp;lr;Hpt=8ef8_116;CxtId=3;TRC=ffffffff-ffffffff;X-HwB2bUaCookie=18614] May 3 15:23:12 sipproxy /usr/sbin/kamailio[263013]: DEBUG: db_postgres [km_res.c:242]: db_postgres_convert_rows(): [0][8] Column[y_rr]=[sip:<PSTNgw>:5060;transport=udp;lr;Hpt=8ef8_116;CxtId=3;TRC=ffffffff-ffffffff;X-HwB2bUaCookie=18614]

May 3 15:23:12 sipproxy /usr/sbin/kamailio[263013]: DEBUG: db_postgres [km_res.c:234]: db_postgres_convert_rows(): PQgetvalue(0x7fcb4893db50,0,9)=[sip:<<KamailioPSTNgwIP>>;lr=on;ftag=9945501E2B94B883;did=1fc.42f;nat=yes] May 3 15:23:12 sipproxy /usr/sbin/kamailio[263013]: DEBUG: db_postgres [km_res.c:242]: db_postgres_convert_rows(): [0][9] Column[s_rr]=[sip:<<KamailioPSTNgwIP>>;lr=on;ftag=9945501E2B94B883;did=1fc.42f;nat=yes]

May 3 15:23:12 sipproxy /usr/sbin/kamailio[263019]: DEBUG: db_postgres [km_res.c:242]: db_postgres_convert_rows(): [0][10] Column[a_rr]=[sip:<KamailioRegistrarIP>;lr=on;ftag=9945501E2B94B883;did=1fc.7b92] May 3 15:23:12 sipproxy /usr/sbin/kamailio[263019]: DEBUG: db_postgres [km_res.c:234]: db_postgres_convert_rows(): PQgetvalue(0x7fcb4893dbd8,0,11)=[] ```

### Possible Solutions

Respect Route headers for UPDATE messages.

### Additional Information

Current running kamailio 5.5.6 but tried also latest 5.6.4 with same behavior.

``` version: kamailio 5.5.6 (x86_64/linux) 72dbb0 flags: USE_TCP, USE_TLS, USE_SCTP, TLS_HOOKS, USE_RAW_SOCKS, DISABLE_NAGLE, USE_MCAST, DNS_IP_HACK, SHM_MMAP, PKG_MALLOC, Q_MALLOC, F_MALLOC, TLSF_MALLOC, DBG_SR_MEMORY, USE_FUTEX, FAST_LOCK-ADAPTIVE_WAIT, USE_DNS_CACHE, USE_DNS_FAILOVER, USE_NAPTR, USE_DST_BLOCKLIST, HAVE_RESOLV_RES, TLS_PTHREAD_MUTEX_SHARED ADAPTIVE_WAIT_LOOPS 1024, MAX_RECV_BUFFER_SIZE 262144, MAX_URI_SIZE 1024, BUF_SIZE 65535, DEFAULT PKG_SIZE 8MB poll method support: poll, epoll_lt, epoll_et, sigio_rt, select. id: 72dbb0 compiled on 05:48:21 Apr 27 2023 with gcc 11.3.0 ```

* **Operating System**:

``` Distributor ID: Ubuntu Description: Ubuntu 22.04.2 LTS Release: 22.04 Codename: jammy Linux sipproxy 5.15.0-70-generic #77-Ubuntu SMP Tue Mar 21 14:02:37 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux ```

Possibly related bug: https://github.com/kamailio/kamailio/issues/3090