6lowpan: fix NHC entry use-after-free on error path

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CVE-2026-64452 · Microsoft / collected KEV context

cve-program · CVE-2026-64452

• https://git.kernel.org/stable/c/9c2f5c0829a8c8b904dae36be6d8056b719ac605
• https://git.kernel.org/stable/c/80b5c8779acee0550845394fb3e5176a398aa24c
• https://git.kernel.org/stable/c/cc27aea4d454abfb385ee2c9499c78b96db9b728
• https://git.kernel.org/stable/c/a8e3a94711134e898c6021a6b77374efa91b3639
• https://git.kernel.org/stable/c/593b78bb3c7ef0c6e9ae6fdf5afa80a5f7573168
• https://git.kernel.org/stable/c/0beccbcf50de125be5520d0ffc59af4bb8655482
• https://git.kernel.org/stable/c/b713aa0cc344f10f7a9928a230b5f5e780d04078
• https://git.kernel.org/stable/c/1720db928e5a58ca7d75ac1d514c3b73fd7061a7

No related operational record is retained in the current change model.