Invalid link to firmware/overlays README file.

[scotty3785]

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This documentation currently says "Please refer to the README file found alongside the overlay .dtbo files in /boot/firmware/overlays. It is kept up-to-date with additions and changes."

The link to the overlays README returns a 404 error.

[lurch]

Ahhh, looks like the link ought to be https://github.com/raspberrypi/firmware/blob/master/boot/overlays/README - perhaps things got rearranged? ping @popcornmix

[nathan-contino]

Thanks! Fixing this now...

[nathan-contino]

#3823