signed vs unsigned fwupd programs

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fwupd 1.1.0 is configured to understand when to use a signed version

of the EFI binary. If the signed version isn't installed but secure

boot is turned on, it will avoid copying to the EFI system partition.

This allows supporting secure boot even if not turned on at install, or

changed later after install.

In Ubuntu, both fwupd-signed and fwupd are seeded in the default

installation. Nothing is installed to the ESP until it's needed.

In Debian, the package name for the signed version is slightly

different due to different infrastructure. fwupd-signed-$ARCH and

fwupd should both be installed and then things will work similarly

to what's described above.