CVE-2026-74385: nvmet-tcp: check return value of nvmet_tcp_set_queue_sock

In the Linux kernel, the following vulnerability has been resolved:

nvmet-tcp: check return value of nvmettcpsetqueuesock

The return value of nvmettcpsetqueuesock() is currently ignored in nvmettcptlshandshakedone(). If it fails (e.g., due to the socket not being in TCPESTABLISHED state), the socket callbacks will not be properly set, leading to queue and socket leakage.

Fix this by capturing the return value and calling nvmettcpschedulereleasequeue() on failure to ensure proper cleanup.