fix(esp_eth): fix C++ invalid type conversion error (IDFGH-13363)

[stkw0]

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Closes https://github.com/espressif/esp-idf/issues/14265

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[kostaond]

sha=b3f0559b2f72a3e2a28a451fdf9aba3056f7184a

[Alvin1Zhang]

Thanks for contribution again, changes have been merged with https://github.com/espressif/esp-idf/commit/ad9cdcd11a5b3b27f8f27aa0b835bf46b4e6912e.