[redfish] Report a missing firmware inventory member as an error code

[nikamirrr]

Why I did it

redfish_api_get_firmware_version() returned ERR_CODE_OK for a Redfish response that carries no Version. exec_curl_cmd() only translates cURL-level failures and HTTP 401 into error codes, so a 4xx carrying a Redfish error body reaches the caller as success; the absent Version was reported only as an ERROR log line.

That matters to any caller that discovers which inventory member belongs to a component by probing candidate IDs and keeping the first one that resolves. Such a probe cannot distinguish "this ID exists" from "this ID does not", so it accepts the first candidate unconditionally and never falls through. The observable effects are a component version reported as N/A, firmware update targeting a member that does not exist, and an ERROR logged on every access.

How I did it

Set ret from the Redfish reason when the response carries no Version: ERR_CODE_URI_NOT_FOUND for ResourceNotFound / ResourceMissingAtURI, ERR_CODE_UNEXPECTED_RESPONSE otherwise. Demoted the log to notice, since a probe that is expected to miss must not emit ERROR.

The classification reads the Redfish reason rather than the HTTP status deliberately. A service may answer a GET for a missing inventory member with 400 instead of 404, and 400 is also what it returns for a genuinely malformed request, so the status alone cannot identify the case. Body inspection is already the contract elsewhere in this file - redfish_api_get_eeprom_info() classifies the same way.

The reason is matched on the Reason component of the Base.<ver>.<Reason> code rather than by substring, so an unrelated code that happens to contain one of these names is not misclassified.

redfish_api_get_firmware_list() already maps any non-OK code to version "N/A", so it is unaffected.

How to verify it

test_get_bmc_version_missing_id covers a 400 ResourceMissingAtURI body. test_get_bmc_version_no_version_field covers the other new branch twice: an error the caller cannot act on, and a 200 body that simply omits Version, both reported as ERR_CODE_UNEXPECTED_RESPONSE with version 'N/A'. 120 tests pass across redfish_client_test.py and bmc_base_test.py.

On hardware, a component whose version previously read N/A is reported correctly, and the 'Version not found in Redfish response' ERROR no longer appears in syslog.

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[mssonicbld]

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