Debugger: Use FilePath for core files and surroundings

Change-Id: Icd648147ee907a2c5ba75042f003229bbd9226fe
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/debugger/cdb/cdbengine.cpp

@@ -419,7 +419,7 @@ void CdbEngine::setupEngine()
         }
         break;
     case AttachToCore:
-        debugger.addArgs({"-z", sp.coreFile});
+        debugger.addArgs({"-z", sp.coreFile.path()});
         break;
     default:
         handleSetupFailure(QString("Internal error: Unsupported start mode %1.").arg(sp.startMode));