Ok so with minor change to uart for serial output your build runs on the router.
BusyBox v1.36.0 (2023-04-02 22:25:00 UTC) built-in shell (ash)
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|_______|| __|_____|__|__||________||__| |____|
|__| W I R E L E S S F R E E D O M
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OpenWrt SNAPSHOT, r22461-49eff508c4
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=== WARNING! =====================================
There is no root password defined on this device!
Use the "passwd" command to set up a new password
in order to prevent unauthorized SSH logins.
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root@OpenWrt:/# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
root@OpenWrt:/# ls -l /sys/class/net/
lrwxrwxrwx 1 root root 0 Jan 1 1970 lo -> ../../devices/virtual/net/lo
However without any ethernet ports, as expected. The Wifi will not be too diifficult get up but I suspect the ethernet is going to be a headache
[ 5.125502] kmodloader: 1 module could not be probed
[ 5.125616] kmodloader: - qca-nss-dp - 0
[ 31.205213] l11: disabling
Maybe some help from guys at this thread,
IPQ807X NSS Build - Community Builds, Projects & Packages - OpenWrt Forum
They seemed to have figured out qca_nss_dp for that router.