remove write lock which is no longer required by buffer manager API

benchmarks/sequentialThroughput.c

@@ -126,9 +126,7 @@ int main(int argc, char ** argv) {
 
     for(long i =0; i < page_count; i++) {
       Page * p = loadUninitializedPage(-1, i);
-      writelock(p->rwlatch,0);
       stasis_dirty_page_table_set_dirty(stasis_runtime_dirty_page_table(), p);
-      unlock(p->rwlatch);
       releasePage(p);
     }
   }