Debugger: Make ElfReader work remotely

This does not use the mmap optimization so it might turn out to be
too expensive for large files and slow connections. For now it seems
good enough for docker and normal test cases.

Change-Id: I0ba09bdbd6aac977209494a33099479f1f8eec0a
Reviewed-by: Christian Stenger <christian.stenger@qt.io>
Reviewed-by: Orgad Shaneh <orgads@gmail.com>

src/plugins/debugger/debuggerengine.cpp

@@ -2778,7 +2778,7 @@ void CppDebuggerEngine::validateRunParameters(DebuggerRunParameters &rp)
             break;
         }
 
-        Utils::ElfReader reader(rp.symbolFile.toString());
+        ElfReader reader(rp.symbolFile);
         const ElfData elfData = reader.readHeaders();
         const QString error = reader.errorString();