custom_calyptia: fix using after freed memory(#8530)

[nokute78]

This patch is to fix #8530 and release ctx when initialization failed.

#8530 points following code is vulnerable.
Because setup_cloud_output can release ctx and it means ctx->o can be freed memory.

        ctx->o = setup_cloud_output(config, ctx);

        if (ctx->o == NULL) {
            return -1;
        }

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