libutils: turn on -Werror

- Deal with some -Wunused issues
- Override PRI macros (windows)
- Revert use of PRI macros on off64_t (linux)
- Deal with a gnu++11 complaince issue

Change-Id: Ie66751293bd84477a5a6dfd8a57e700a16e36964
diff --git a/libutils/LinearAllocator.cpp b/libutils/LinearAllocator.cpp
index a07a291..8b90696 100644
--- a/libutils/LinearAllocator.cpp
+++ b/libutils/LinearAllocator.cpp
@@ -92,7 +92,7 @@
         : mNextPage(0)
     {}
 
-    void* operator new(size_t size, void* buf) { return buf; }
+    void* operator new(size_t /*size*/, void* buf) { return buf; }
 
     void* start() {
         return (void*) (((size_t)this) + sizeof(Page));
@@ -103,7 +103,7 @@
     }
 
 private:
-    Page(const Page& other) {}
+    Page(const Page& /*other*/) {}
     Page* mNextPage;
 };