Allow setting kernel_start_message in device templates of aaeon-UPN-EHLX4RE-A10-0864 and minnowboard-common type
requested to merge collabora-staging-aaeon-and-minnowboard-do-not-override-kernel-start-message into collabora/staging
Allow setting kernel_start_message in devices of aaeon-UPN-EHLX4RE-A10-0864 and minnowboard-common type
Because those device type templates did not use the default()
filter they always overwrote the value of kernel_start_message
even if a derived template set it. Now the value of "Booting in blind mode"
would only be used if the device template did not set it.