Fix a warning about calling virtual method from d'tor

Fix the following clang-tidy warning:
Call to virtual method 'IosRunner::stop' during destruction bypasses
virtual dispatch [clang-analyzer-optin.cplusplus.VirtualCall]

Remove the reimplementation of IosRunSupport::stop(), as it was
calling base implementation. Make base IosRunner::stop() a final
method.

Change-Id: I8e57a6dd6a44d2a6f00f5af96a11530f62c92429
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/ios/iosrunner.cpp

@@ -369,11 +369,6 @@ void IosRunSupport::start()
     IosRunner::start();
 }
 
-void IosRunSupport::stop()
-{
-    IosRunner::stop();
-}
-
 //
 // IosQmlProfilerSupport
 //