DAOS-15961 cart: Reorganize how envs are handled (#14504)

[frostedcmos]

Cherry-pick of 2 PRs from master:
993558e - env reorg
7f80548 - bugfix to env reorg

Change to how cart deals with envariables:

• env list is now controlled by CRT_ENV_LIST macro in crt_types_internal.h
• all envs stored in structure generated from CRT_ENV_LST (crrt_genv) now, ENV is read out at crt_env_init() time and env strings deallocated at crt_env_fini().
• accsor functions/macros crt_env_init/fini/get/dump are provided.
• string-type envs no longer need to be freed after retrieval.
• Change cart utility function to populate crt_init_options_t instead of setting and querying env.

With this change, any env to be used will need to appear on the list first, ensuring it gets dumped as well as ensuring proper name usage later. Env name typos when using crt_env_get() will now result in compile time errors

Required-githooks: true

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[github-actions]

Ticket title is 'Reorganize how cart handles envariables'
Status is 'Awaiting backport'
Job should run at elevated priority (1)
https://daosio.atlassian.net/browse/DAOS-15961

[daosbuild1]

Test stage Build on Leap 15.5 with Intel-C and TARGET_PREFIX completed with status FAILURE. https://build.hpdd.intel.com//job/daos-stack/job/daos/view/change-requests/job/PR-14887/1/execution/node/358/log

[daosbuild1]

Test stage Build on Leap 15.5 with Intel-C and TARGET_PREFIX completed with status FAILURE. https://build.hpdd.intel.com//job/daos-stack/job/daos/view/change-requests/job/PR-14887/2/execution/node/386/log

[daosbuild1]

Test stage Functional on EL 8.8 completed with status FAILURE. https://build.hpdd.intel.com//job/daos-stack/job/daos/view/change-requests/job/PR-14887/4/execution/node/1209/log

[daltonbohning]

ftest LGTM

[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-14887/7/execution/node/1447/log

[frostedcmos]

Test stage Functional Hardware Medium completed with status FAILURE. https://build.hpdd.intel.com//job/daos-stack/job/daos/view/change-requests/job/PR-14887/7/execution/node/1447/log

Failure in Test Hardware / Functional Hardware Medium / FTEST_osa.OSAOfflineReintegration.1-./osa/offline_reintegration.py:OSAOfflineReintegration.test_osa_offline_reintegration_without_checksum;run-agent_config-transport_config-aggregation-blank_node-checksum-container-dmg-hosts-ior-clientslots-iorflags-loop_test-mdtest-client_processes-wr_size-32K-pool-pool_capacity-rebuild-server_config-engines-0-storage-0-1-setup-snapshot-test_obj_class-test_rf-timeouts-6a10

due to https://daosio.atlassian.net/browse/DAOS-15608