qa: accept client returning pool id for layout

qa: accept client returning pool id for layout

Resolving this failure:

	2020-10-30T22:52:25.898 INFO:tasks.cephfs_test_runner:test_subvolume_group_create_with_desired_data_pool_layout (tasks.cephfs.test_volumes.TestSubvolumeGroups) ... FAIL
	2020-10-30T22:52:25.898 INFO:tasks.cephfs_test_runner:
	2020-10-30T22:52:25.899 INFO:tasks.cephfs_test_runner:======================================================================
	2020-10-30T22:52:25.899 INFO:tasks.cephfs_test_runner:FAIL: test_subvolume_group_create_with_desired_data_pool_layout (tasks.cephfs.test_volumes.TestSubvolumeGroups)
	2020-10-30T22:52:25.899 INFO:tasks.cephfs_test_runner:----------------------------------------------------------------------
	2020-10-30T22:52:25.899 INFO:tasks.cephfs_test_runner:Traceback (most recent call last):
	2020-10-30T22:52:25.900 INFO:tasks.cephfs_test_runner:  File "/home/teuthworker/src/github.com_batrick_ceph_cephfs-qa-reorg/qa/tasks/cephfs/test_volumes.py", line 568, in test_subvolume_group_create_with_desired_data_pool_layout
	2020-10-30T22:52:25.900 INFO:tasks.cephfs_test_runner:    self.assertEqual(desired_pool, new_pool)
	2020-10-30T22:52:25.900 INFO:tasks.cephfs_test_runner:AssertionError: '34' != 'new_pool'
	2020-10-30T22:52:25.900 INFO:tasks.cephfs_test_runner:- 34
	2020-10-30T22:52:25.900 INFO:tasks.cephfs_test_runner:+ new_pool

Fixes: https://tracker.ceph.com/issues/23718
Signed-off-by: Patrick Donnelly <pdonnell@redhat.com>