The test recently started to fail (likely do to a recent change to
"x86/ioapic.c). According to Nitesh, it's not required to keep this
test running with TCG, and we already check it with KVM on Travis,
so let's simply disable it here now.

Message-Id: <20191205151610.19299-1-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>