nvmet: use invalid cmd opcode helper

In the NVMeOF block device backend, file backend, and passthru backend
we reject and report the commands if opcode is not handled.

Use the previously introduced helper in the passthru backend to make the
error message uniform.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/nvme/target/passthru.c

@@ -494,7 +494,7 @@ u16 nvmet_parse_passthru_admin_cmd(struct nvmet_req *req)
 		return nvmet_setup_passthru_command(req);
 	default:
 		/* Reject commands not in the allowlist above */
-		return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
+		return nvmet_report_invalid_opcode(req);
 	}
 }