Fix strftime() usage in pool_pools().
Fix strftime() usage in pool_pools().

The buffer is not large enough as expected by the second parameter.
This is not harmless because the format string will not produce longer
result string than the buffer.

Per Coverity report 1111426 "Out-of-bounds access".

treasure-data/prestogres,treasure-data/prestogres,treasure-data/prestogres,treasure-data/prestogres,treasure-data/prestogres,treasure-data/prestogres,treasure-data/prestogres