qemuxml2argvtest: Add test cases covered only by qemuxml2xmltest - part 1

qemuxml2argvtest: Add test cases covered only by qemuxml2xmltest - part 1

There were plenty of test cases invoked only from qemuxml2xmltest but
not from qemuxml2argvtest, either by accident or it was deemed unneeded.

Bulk-add all test cases which fit the above description which don't
require faking the network driver. Use same invocation as present in
qemuxml2xmltest.

Arguably in certain cases we could move the test case to
genericxml2xmltest, but this covers the cases when that would not be
appropriate.

Tests requiring the network driver will be bulk-added when the fake
network driver will be implemented.

This patch also allows the use of FLAG_SKIP_CONFIG_ACTIVE in
qemuxml2argvtest although the flag will be dormant for now.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>