Instead of hardcoding the A/B slot selection, allow an optional
environment variable (LAVA_FASTBOOT_CMD) for devices that need it.
This is used for sm8350-hdk to select slot A, but can be omitted
for devices that don’t support A/B slots.
Update the lava-trigger container to pull in
1b521e7b38.
Signed-off-by: Valentine Burley <valentine.burley@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/37478>