guest_agent: Domfsfreeze domfsthaw fix (#6549)

* domfsfreeze_domfsthaw: Add a fail pattern for frozen state check

When vm is in frozen state, running a agent command should fail
with clear error message. The error message varies depending on
the libvirt and qemu versions. The previos fail patterns misses
the error message on RHEL9.0

* domfsfreeze_domfsthaw: Thaw vm filesystems before cleanup

If the test fails between domfsfreeze and domfsthaw, cleanup will
fail because it tries to remove files in vm when vm is frozen.

Author: fangge1212

libvirt/tests/src/virsh_cmd/domain/virsh_domfsfreeze_domfsthaw.py

@@ -136,8 +136,9 @@ def run_agent_command_when_frozen(vm_name, command_name="domtime"):
         """
         test.log.info("TEST_STEP: Run qemu guest agent command when frozen.")
         fail_patts = [
-            r"error: guest agent command failed: unable to execute QEMU agent command '\S+': Command guest-get-time has been disabled: the command is not allowed",
-            r"error: internal error: unable to execute QEMU agent command '\S+': Command guest-get-time has been disabled: the command is not allowed",
+            r"error: guest agent command failed: unable to execute QEMU agent command '\S+': Command \S+ has been disabled: the command is not allowed",
+            r"error: internal error: unable to execute QEMU agent command '\S+': Command \S+ has been disabled: the command is not allowed",
+            r"error: internal error: unable to execute QEMU agent command '\S+': Command \S+ has been disabled: the agent is in frozen state",
         ]
 
         virsh_command = eval("virsh.%s" % command_name)
@@ -240,6 +241,7 @@ def cleanup(session, mountpoints, test_file):
                 check_thaw(session, freezed_mountpoints, test_file)
                 run_agent_command_when_thawed(vm_name)
         finally:
+            virsh.domfsthaw(vm_name, ignore_status=True)
             cleanup(session, freezed_mountpoints, test_file)
             session.close()
     finally: