BuildManager: Provide context of earlier build steps to init

This information can be used to get information from earlier steps,
which e.g. queried for android devices to deploy to.

Change-Id: Iefe1c9443915cb6211f86f98ff7aaf3cb75145ba
Reviewed-by: Niels Weber <niels.weber@theqtcompany.com>

src/plugins/qbsprojectmanager/qbscleanstep.cpp

@@ -80,8 +80,9 @@ QbsCleanStep::~QbsCleanStep()
     }
 }
 
-bool QbsCleanStep::init()
+bool QbsCleanStep::init(QList<const BuildStep *> &earlierSteps)
 {
+    Q_UNUSED(earlierSteps);
     if (static_cast<QbsProject *>(project())->isParsing() || m_job)
         return false;