expose set_skip_stats_update_on_db_open to C bindings

Summary:
It would be super helpful to not have to recompile rocksdb to get this performance tweak for mechanical disks.

I have signed the CLA.
Closes https://github.com/facebook/rocksdb/pull/2718

Differential Revision: D5606994

Pulled By: yiwu-arbug

fbshipit-source-id: c05e92bad0d03bd38211af1e1ced0d0d1e02f634

db/c.cc

@@ -2102,6 +2102,10 @@ void rocksdb_options_enable_statistics(rocksdb_options_t* opt) {
   opt->rep.statistics = rocksdb::CreateDBStatistics();
 }
 
+void rocksdb_options_set_skip_stats_update_on_db_open(rocksdb_options_t* opt, unsigned char val) {
+  opt->rep.skip_stats_update_on_db_open = val;
+}
+
 void rocksdb_options_set_num_levels(rocksdb_options_t* opt, int n) {
   opt->rep.num_levels = n;
 }

include/rocksdb/c.h

@@ -763,6 +763,8 @@ rocksdb_options_set_max_bytes_for_level_multiplier_additional(
     rocksdb_options_t*, int* level_values, size_t num_levels);
 extern ROCKSDB_LIBRARY_API void rocksdb_options_enable_statistics(
     rocksdb_options_t*);
+extern ROCKSDB_LIBRARY_API void rocksdb_options_set_skip_stats_update_on_db_open(
+    rocksdb_options_t* opt, unsigned char val);
 
 /* returns a pointer to a malloc()-ed, null terminated string */
 extern ROCKSDB_LIBRARY_API char* rocksdb_options_statistics_get_string(