Add rocr namespace to core header and impl files

Change-Id: I1e1b33f9bba1078d049bc19797889988c3e43360

runtime/hsa-runtime/core/common/shared.cpp

@@ -42,7 +42,9 @@
 
 #include "core/common/shared.h"
 
+namespace rocr {
 namespace core {
 std::function<void*(size_t, size_t, uint32_t)> BaseShared::allocate_ = nullptr;
 std::function<void(void*)> BaseShared::free_ = nullptr;
-}
+}   // namespace core
+}   // namespace rocr