util/qemu-config: Fix "query-command-line-options" to provide the right values

util/qemu-config: Fix "query-command-line-options" to provide the right values

The "query-command-line-options" command uses a hand-crafted list
of options that should be returned for the "machine" parameter.
This is pretty much out of sync with reality, for example settings
like "kvm_shadow_mem" or "accel" are not parameters for the machine
anymore. Also, there is no distinction between the targets here, so
e.g. the s390x-specific values like "loadparm" in this list also
show up with the other targets like x86_64.

Let's fix this now by geting rid of the hand-crafted list and by
querying the properties of the machine classes instead to assemble
the list.

Fixes: 0a7cf217d8 ("fix regression of qmp_query_command_line_options")
Message-Id: <20221111141323.246267-1-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>