[Scarthgap] Build broken: missing DTB for kernel 6.1

[antoinefaure]

Hi,

I am using meta-raspberrypi on the scarthgap release branch. I have a custom machine based on the Raspberry Pi 4, with the following change: PREFERRED_VERSION_linux-raspberrypi ?= "6.1.%"

The build was recently broken due to a missing dtbo file:

| make[2]: *** No rule to make target 'arch/arm64/boot/dts/overlays/vc4-kms-dsi-ili9881-7inch.dtbo'.  Stop.
| make[1]: *** [/workspaces/OmniOS/build/tmp/work-shared/raspberrypi4-recorder/kernel-source/scripts/Makefile.build:500: arch/arm64/boot/dts/overlays] Error 2
| make: *** [/workspaces/OmniOS/build/tmp/work-shared/raspberrypi4-recorder/kernel-source/Makefile:1474: overlays/vc4-kms-dsi-ili9881-7inch.dtbo] Error 2
| ERROR: oe_runmake failed
| WARNING: exit code 1 from a shell command.
ERROR: Task (/workspaces/OmniOS/meta-raspberrypi/recipes-kernel/linux/linux-raspberrypi_6.1.bb:do_compile) failed with exit code '1'

To reproduce simply checkout the scarthgap branch, build an image for a Raspberry Pi 4 with a 6.1 Kernel.

The regression seem to have been introduced by this commit. The dtbo doesn't exist for the 6.1 kernel.