fix log err
fix log err

Summary: Closes https://github.com/facebook/rocksdb/pull/2206

Differential Revision: D5054222

Pulled By: yiwu-arbug

fbshipit-source-id: d8742bda1bf3e76d7b68eeb86df4608031b5cbc8

vmx/rocksdb,Andymic/rocksdb,SunguckLee/RocksDB,SunguckLee/RocksDB,Andymic/rocksdb,vmx/rocksdb,SunguckLee/RocksDB,SunguckLee/RocksDB,bbiao/rocksdb,SunguckLee/RocksDB,vmx/rocksdb,bbiao/rocksdb,SunguckLee/RocksDB,vmx/rocksdb,Andymic/rocksdb,bbiao/rocksdb,vmx/rocksdb,Andymic/rocksdb,Andymic/rocksdb,Andymic/rocksdb,bbiao/rocksdb,SunguckLee/RocksDB,bbiao/rocksdb,vmx/rocksdb,Andymic/rocksdb,Andymic/rocksdb,bbiao/rocksdb,bbiao/rocksdb,bbiao/rocksdb,SunguckLee/RocksDB,vmx/rocksdb,vmx/rocksdb