Remove unnecessary status check in TableCache::NewIterator

Summary:
While investigating the usage of `new_table_iterator_nanos` perf counter, I saw some code was wrapper around with unnecessary status check ... so removed it.
Closes https://github.com/facebook/rocksdb/pull/3120

Differential Revision: D6229181

Pulled By: sagar0

fbshipit-source-id: f8a44fe67f5a05df94553fdb233b21e54e88cc34

db/table_cache.cc

@@ -180,7 +180,6 @@ InternalIterator* TableCache::NewIterator(
   bool create_new_table_reader = false;
   TableReader* table_reader = nullptr;
   Cache::Handle* handle = nullptr;
-  if (s.ok()) {
   if (table_reader_ptr != nullptr) {
     *table_reader_ptr = nullptr;
   }
@@ -222,7 +221,6 @@ InternalIterator* TableCache::NewIterator(
       }
     }
   }
-  }
   InternalIterator* result = nullptr;
   if (s.ok()) {
     if (options.table_filter &&