Sorry for the late reply but have been tied up. I've tried your compiled image which leads to good and bad news... The card booted and is using hs400es mode though the image is unstable. Networking seems to be broken and when I run any type of commands geared towards networking to troubleshoot, the whole board freezes. After booting in again I see the below from dmesg. I noticed the image is at 5.4.7 where I was testing 5.4.6. So unsure if something released in 5.4.7 caused this issue or if your changes are causing the null pointer. :shrug:
[ 56.465005] Unable to handle kern