RemoteLinux: Make build/deploysteps constructible by id only

Will help to remove some of the remaining hard dependencies of Qnx and
Boot2Qt on RemoteLinux.

Change-Id: I1a327249a9b2903b5b9d869cb9cd60bb50250a5c
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

src/plugins/remotelinux/tarpackagecreationstep.cpp

@@ -25,6 +25,8 @@
 
 #include "tarpackagecreationstep.h"
 
+#include "remotelinux_constants.h"
+
 #include <projectexplorer/buildmanager.h>
 #include <projectexplorer/deploymentdata.h>
 #include <projectexplorer/project.h>
@@ -386,7 +388,7 @@ QVariantMap TarPackageCreationStep::toMap() const
 
 Utils::Id TarPackageCreationStep::stepId()
 {
-    return "MaemoTarPackageCreationStep";
+    return Constants::TarPackageCreationStepId;
 }
 
 QString TarPackageCreationStep::displayName()