options: Fix coverity issues

Summary:
options/cf_options.cc:
 77      memtable_insert_with_hint_prefix_extractor(

CID 1396208 (#1 of 1): Uninitialized scalar field (UNINIT_CTOR)
2. uninit_member: Non-static class member info_log_level is not initialized in this constructor nor in any functions that it calls.
Closes https://github.com/facebook/rocksdb/pull/3106

Differential Revision: D6874689

Pulled By: sagar0

fbshipit-source-id: b5cd2d13915fd86d87260050f9c5d117615bbe30

options/cf_options.cc

@@ -42,6 +42,7 @@ ImmutableCFOptions::ImmutableCFOptions(const ImmutableDBOptions& db_options,
       info_log(db_options.info_log.get()),
       statistics(db_options.statistics.get()),
       rate_limiter(db_options.rate_limiter.get()),
+      info_log_level(db_options.info_log_level),
       env(db_options.env),
       allow_mmap_reads(db_options.allow_mmap_reads),
       allow_mmap_writes(db_options.allow_mmap_writes),