Don't duplicate embedded code objects (#1991)

If the code object is embedded in an already mapped file, and the
lifetime of the mapped file exceeds the lifetime of the executable,
we do not need to make a copy of the binary.

This allows the ROCR to present the code object URI as
file:///path/to/file#offset=X&size=Y.

[ROCm/hip commit: 9de5e90ab5]

projects/hip/include/hip/hcc_detail/program_state.hpp

@@ -73,6 +73,9 @@ public:
     hsa_executable_t load_executable(const char*, const size_t,
                                      hsa_executable_t,
                                      hsa_agent_t);
+    hsa_executable_t load_executable_no_copy(const char*, const size_t,
+                                             hsa_executable_t,
+                                             hsa_agent_t);
 
     void* global_addr_by_name(const char* name);