Add internal_merge_point_lookup_count perfstats to c interface (#13599)

Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/13599

Reviewed By: virajthakur

Differential Revision: D74586452

Pulled By: cbi42

fbshipit-source-id: 58f31d96c040ae465afa1caba8cbb7434c72a366

db/c.cc

@@ -4358,6 +4358,8 @@ uint64_t rocksdb_perfcontext_metric(rocksdb_perfcontext_t* context,
       return rep->internal_recent_skipped_count;
     case rocksdb_internal_merge_count:
       return rep->internal_merge_count;
+    case rocksdb_internal_merge_point_lookup_count:
+      return rep->internal_merge_point_lookup_count;
     case rocksdb_get_snapshot_time:
       return rep->get_snapshot_time;
     case rocksdb_get_from_memtable_time:

include/rocksdb/c.h

@@ -1883,7 +1883,8 @@ enum {
   rocksdb_blob_decompress_time,
   rocksdb_internal_range_del_reseek_count,
   rocksdb_block_read_cpu_time,
-  rocksdb_total_metric_count = 79
+  rocksdb_internal_merge_point_lookup_count,
+  rocksdb_total_metric_count = 80
 };
 
 extern ROCKSDB_LIBRARY_API void rocksdb_set_perf_level(int);