tests: Fix check-report-qtest-% target

Commit e253c28 ("tests: Fix how qom-test is run") introduced
$(qtest-generic-y) and used it for check-qtest-% target, but did not
update check-report-qtest-%. This causes check-report-qtest-aarch64.xml
target to fail with a gtester usage error for lack of test arguments.

Fix this by adding $(qtest-generic-y) in check-report-qtest-%.
Also add it in check-clean target, spotted by Markus.

Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
