Virtual_disk: fix avc denials caused by denied file access (#6559)

Some avc denails will occur but not affect the feature function in
several virtual_disk.nbd cases. This file path is random, So update
them to a selinux allowed one.

Signed-off-by: meinaLi <[email protected]>

Author: meinaLi

libvirt/tests/cfg/virtual_disks/virtual_disks_nbd.cfg

@@ -26,10 +26,11 @@
                     deleteExisted = "no"
                     virt_disk_check_partitions = "no"
                     snapshot_name1 = "snap1"
-                    snapshot_name1_file = "/tmp/${snapshot_name1}-testvm.qcow2"
+                    snapshot_path = "/var/lib/libvirt/images"
+                    snapshot_name1_file = "${snapshot_path}/${snapshot_name1}-testvm.qcow2"
                     snapshot_name2 = "snap2"
-                    snapshot_name2_mem_file = "/tmp/${snapshot_name2}-testvm-mem"
-                    snapshot_name2_disk_file = "/tmp/${snapshot_name2}-testvm.qcow2"
+                    snapshot_name2_mem_file = "${snapshot_path}/${snapshot_name2}-testvm-mem"
+                    snapshot_name2_disk_file = "${snapshot_path}/${snapshot_name2}-testvm.qcow2"
         - lifecycle_operate:
     variants:
         - enable_export: