I've managed to get my patches into vanilla kernel about month back, so the openwrt will start use them automatically when it gets to next future stable branch (5.4+ probably, .. long time ahead ).
But about a week ago one of my patch was backported to all stable trees including the one openwrt is using, so I guessed I could rebase my patches.
The autobalancing function was removed for the vanilla, so you must to change the interrupts by hand, for example:
echo 1 > /proc/irq/73/smp_affinity
echo 2 > /proc/irq/75/smp_affinity
(the value is bitmask, just google "kernel bitmask affinity" or something like this).
Copy the files into target/linux/lantiq/patches-4.19 of your openwrt directory and reconfigure the kernel. The kernel I based this is 4.19.65 and the openwrt is current git version (old about a day). Don't forget pastebin may eat the last empty line.