ProjectExplorer: Pass Id to BuildStep constructor

Allows to use constants in fewer places, similar to what e.g.
RunConfiguration does.

Change-Id: I9d049128206c4acf0ce14b06b66d6c090a7c5242
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

src/plugins/ios/iosbuildstep.cpp

@@ -163,8 +163,8 @@ private:
     QLineEdit *m_extraArgumentsLineEdit;
 };
 
-IosBuildStep::IosBuildStep(BuildStepList *parent) :
-    AbstractProcessStep(parent, IOS_BUILD_STEP_ID)
+IosBuildStep::IosBuildStep(BuildStepList *parent, Id id)
+    : AbstractProcessStep(parent, id)
 {
     setDefaultDisplayName(QCoreApplication::translate("GenericProjectManager::Internal::IosBuildStep",
                                                       IOS_BUILD_STEP_DISPLAY_NAME));