I think a good first step would be to try that reverting the change
would actually fix the issue for you. Something like the below should do
the trick.

That's indeed the case, reverting that commit makes everything work again 
on 5.7.1. We have five other unrelated patches as well, our tree is 
available at 
https://gerrit.cesnet.cz/plugins/gitiles/github/torvalds/linux/+log/aabb023ef197c4b365a4404bca2fd8cd0c227835 
.

Also, can you point out which exact DTS file it is that you
see this problem with?

It's armada-388-clearfog-base.dts, and we have some small additions on top 
of that. The only modification which looks relevant that we ship is:

/ {
        gpio_i2c {
                compatible = "i2c-gpio";
                sda-gpios = <&gpio0 25 (GPIO_ACTIVE_HIGH | 
GPIO_OPEN_DRAIN)>;
                scl-gpios = <&gpio0 24 (GPIO_ACTIVE_HIGH | 
GPIO_OPEN_DRAIN)>;
                i2c-gpio.delay-us = <1>;
                #address-cells = <1>;
                #size-cells = <0>;
        };
};

&uart1_pins {
        status = "disabled";
};

&uart1 {
        status = "disabled";
};

With kind regards,
Jan