add case for virtio-mem with memory backing type

[nanli1]

VIRT-299164: Virtio-mem memory device with various memory backing type

Signed-off-by: nanli [email protected]

RHEL9 + x86

avocado run --vt-type libvirt --test-runner=runner --vt-machine-type q35 memory.devices.virtio_mem.memory_backing_type

 (1/7) type_specific.io-github-autotest-libvirt.memory.devices.virtio_mem.memory_backing_type.with_numa.alloc_ondemand.file: PASS (86.39 s)
 (2/7) type_specific.io-github-autotest-libvirt.memory.devices.virtio_mem.memory_backing_type.with_numa.alloc_ondemand.anonymous: PASS (86.36 s)
 (3/7) type_specific.io-github-autotest-libvirt.memory.devices.virtio_mem.memory_backing_type.with_numa.alloc_ondemand.memfd: PASS (86.27 s)
 (4/7) type_specific.io-github-autotest-libvirt.memory.devices.virtio_mem.memory_backing_type.with_numa.alloc_ondemand.undefined: PASS (83.22 s)
 (5/7) type_specific.io-github-autotest-libvirt.memory.devices.virtio_mem.memory_backing_type.with_numa.set_hugepage.file: PASS (83.49 s)
 (6/7) type_specific.io-github-autotest-libvirt.memory.devices.virtio_mem.memory_backing_type.with_numa.set_hugepage.memfd: PASS (84.64 s)
 (7/7) type_specific.io-github-autotest-libvirt.memory.devices.virtio_mem.memory_backing_type.with_numa.set_hugepage.undefined: PASS (83.01 s)

rhel9 + aarch64 (virtio mem not support on rhel8)

[nanli1]

Feature owner is still updating the polarion case to maker step and matrix be more clear ,

[nanli1]

Feature owner is reviewing the polarion case after reacting