import-trace: introduce InstructionImporter

The InstructionImporter does disassemble the binary and generate read
traces for every instruction byte executed.

Change-Id: I6b8697c711c009e106ed733c74c6ff8f9bbf8ac5

src/core/util/ElfReader.cc

@@ -48,6 +48,8 @@ void ElfReader::setup(const char* path) {
     return;
   }
 
+  m_filename = std::string(path);
+
   // Evaluate headers
   Elf32_Ehdr ehdr;
   Elf32_Shdr sec_hdr;