ci: Remove kernel module build that slipped in

ci: Remove kernel module build that slipped in

Some changes unintendedly slipped into an unrelated commit before it was
merged.

This caused kernel modules to be built and installed in the ramdisk,
which caused some devices to fail to boot due to the ramdisk size limit
being surpassed.

These changes weren't in effect until a subsequent commit triggered a
rebuild of the ramdisks.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Acked-by: Daniel Stone <daniels@collabora.com>
Fixes: a9560939e07a ("ci: Build-test Panfrost tools")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6167>