bloom_test.cc: include <array> (#5920)

Summary:
Fix build failure on some platforms, reported in issue https://github.com/facebook/rocksdb/issues/5914
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5920

Test Plan: make bloom_test && ./bloom_test

Differential Revision: D17918328

Pulled By: pdillinger

fbshipit-source-id: b822004d4442de0171db2aeff433677783f7b94e

util/bloom_test.cc

@@ -15,6 +15,7 @@ int main() {
 }
 #else
 
+#include <array>
 #include <vector>
 
 #include "logging/logging.h"