commit 184a4a2d82f4f6f3cbcb1015bcdb32bebe73315c
Author: Abhinav Sharma <abhinavsharma@fb.com>
Date:   Thu Sep 14 11:40:08 2017 -0700

    Bump rocksdb submodule

    Summary:
    Bump rocksdb to include the fix for rocksdb.trx_info_rpl

    The bug was introduced in: https://github.com/facebook/rocksdb/pull/2850
    Fixed in: https://github.com/facebook/rocksdb/pull/2881

    update-submodule: rocksdb

    Reviewed By: lth

    Differential Revision: D5834658

    fbshipit-source-id: d1551bf