For some strange reasons the 'swupd' module does not fail if I specify a
non-existing bundle like "xxx". This is inconsistent with other modules, for
example 'dnf'.
The end result is that if someone uses the 'package' module, the result is
inconsistent across OSes: for Fedora trying to install an non-existing module
fails, bot for Clear Linux it just prints a warning and succeeds.
This patch fixes the inconsistent behavior. With this patch 'swupd' will fail
if one tries to install a bundle that does not exist.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>