Fix warning: "Unused non-trivial variable"

[-Wclazy-unused-non-trivial-variable]

Change-Id: Ia99c3de31fd92205f25624ab60e60370c1aa4538
Reviewed-by: Orgad Shaneh <orgads@gmail.com>
Reviewed-by: hjk <hjk@qt.io>

src/plugins/debugger/breakpoint.cpp

@@ -291,7 +291,6 @@ void BreakpointParameters::updateFromGdbOutput(const GdbMi &bkpt)
     QString originalLocation;
     QString file;
     QString fullName;
-    QString internalId;
 
     enabled = true;
     pending = false;