db_bench: --soft_pending_compaction_bytes_limit should set options.soft_pending_compaction_bytes_limit

Summary: Fix a bug that options.soft_pending_compaction_bytes_limit is not actually set with --soft_pending_compaction_bytes_limit

Test Plan: Run db_bench with this parameter and make sure the parameter is set correctly.

Reviewers: anthony, kradhakrishnan, yhchiang, IslamAbdelRahman, igor, rven

Reviewed By: rven

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D52125

db/db_bench.cc

@@ -2548,6 +2548,8 @@ class Benchmark {
     }
     options.soft_rate_limit = FLAGS_soft_rate_limit;
     options.hard_rate_limit = FLAGS_hard_rate_limit;
+    options.soft_pending_compaction_bytes_limit =
+        FLAGS_soft_pending_compaction_bytes_limit;
     options.hard_pending_compaction_bytes_limit =
         FLAGS_hard_pending_compaction_bytes_limit;
     options.delayed_write_rate = FLAGS_delayed_write_rate;