Revert "Report cpu usage using time command"
Revert "Report cpu usage using time command"

Summary:
This reverts commit 97ec8a134968c342cdf7244352220bb292fd950c.
Closes https://github.com/facebook/rocksdb/pull/2136

Differential Revision: D4870610

Pulled By: maysamyabandeh

fbshipit-source-id: cdbfba135b065562f38f704f350a9a4e63a9a122

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