DAOS-13786 client: pool_free take rdlock for dp_co_list check

[kccain]

Cherry-pick of to release/2.4 branch, a fix for Coverity CID 1444801

Required-githooks: true

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[github-actions]

Bug-tracker data:
Ticket title is '[coverity] 1444801 Data race condition'
Status is 'In Review'
Labels: 'coverity,required_for_code_freeze'
Job should run at elevated priority (1)
https://daosio.atlassian.net/browse/DAOS-13786

[daosbuild1]

LGTM. No errors found by checkpatch.

[daosbuild1]

Test stage Functional Hardware Medium completed with status FAILURE. https://build.hpdd.intel.com//job/daos-stack/job/daos/view/change-requests/job/PR-12473/1/execution/node/1289/log

[kccain]

Build 1 failures appear to be unrelated, existing failures

1. daos_racer https://daosio.atlassian.net/browse/DAOS-13341
   https://build.hpdd.intel.com/job/daos-stack/job/daos/job/PR-12473/1/testReport/junit/FTEST_daos_racer/DaosRacerTest/Test_Hardware___Functional_Hardware_Medium___1___daos_racer_simple_py_DaosRacerTest_test_daos_racer_simple_run_daos_racer_hosts_server_config_engines_0_storage_0_1_2fbf/

2. repeated -DER_TIMEDOUT seen during execution of a pool create command, and seem to be instances of the existing bugs https://daosio.atlassian.net/browse/DAOS-13570 (duplicate of https://daosio.atlassian.net/browse/DAOS-13678).

https://build.hpdd.intel.com/job/daos-stack/job/daos/job/PR-12473/1/testReport/junit/FTEST_aggregation/DaosAggregationBasic/Test_Hardware___Functional_Hardware_Medium___1___aggregation_basic_py_DaosAggregationBasic_test_basic_aggregation_run_container_hosts_ior_client_processes_iorflags_objectclass_oclass_SX_pool_server_config_engines_0_storage_0_1_d5c6/

https://build.hpdd.intel.com/job/daos-stack/job/daos/job/PR-12473/1/testReport/junit/FTEST_aggregation/DaosAggregationBasic/Test_Hardware___Functional_Hardware_Medium___2___aggregation_basic_py_DaosAggregationBasic_test_basic_aggregation_run_container_hosts_ior_client_processes_iorflags_objectclass_oclass_RP_2GX_pool_server_config_engines_0_storage_0_1_c5eb/

https://build.hpdd.intel.com/job/daos-stack/job/daos/job/PR-12473/1/testReport/junit/FTEST_aggregation/AggregationChecksum/Test_Hardware___Functional_Hardware_Medium___1___aggregation_checksum_py_AggregationChecksum_test_aggregationchecksum_run_container_hosts_ior_client_processes_objectclass_SX_transfersize_blocksize_2K_pool_server_config_engines_0_storage_0_1_b17c/

https://build.hpdd.intel.com/job/daos-stack/job/daos/job/PR-12473/1/testReport/junit/FTEST_container/SnapshotAggregation/Test_Hardware___Functional_Hardware_Medium___1___container_snapshot_aggregation_py_SnapshotAggregation_test_snapshot_aggregation_run_container_hosts_ior_pool_server_config_engines_0_storage_0_1_9cfa/

https://build.hpdd.intel.com/job/daos-stack/job/daos/job/PR-12473/1/testReport/junit/FTEST_pool/PoolCreateTests/Test_Hardware___Functional_Hardware_Medium___1___pool_create_py_PoolCreateTests_test_create_no_space_loop_run_hosts_pool_1_pool_2_server_config_engines_0_storage_0_1_timeouts_ec9e/

[kccain]

As happened on another release/2.4 cherry pick PR, I need to fix up the unintended file changes that update the copyright on otherwise unmodified files. The only file to be changed in this patch is src/pool/cli.c. I will force push that change next and propose that the existing test build 1 be used, rather than pushing the identical logic change through another lengthy round of CI testing.

[daosbuild1]

LGTM. No errors found by checkpatch.