Function parity_rocksdb::rocksdb_ffi::rocksdb_writebatch_merge_cf

pub unsafe extern "C" fn rocksdb_writebatch_merge_cf(
    batch: *const DBWriteBatchOpaque, 
    cf: *const DBCFHandleOpaque, 
    key: *const u8, 
    klen: usize, 
    val: *const u8, 
    vlen: usize
)