Nim: Restore init() override

The usages if validate() disappeared in the following commits:
ec75575e64
0d185a0ad3

Restore a call to validate() from init() reimplementation.
Inline validate() body there.

Change-Id: I5999cc98345cd4d15138eb891c92d9bb9de00027
Reviewed-by: hjk <hjk@qt.io>

src/plugins/nim/project/nimbletaskstep.cpp

@@ -45,7 +45,7 @@ private:
     void onDataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight, const QVector<int> &roles);
     void uncheckedAllDifferentFrom(QStandardItem *item);
 
-    bool validate();
+    bool init() override;
 
     StringAspect m_taskName{this};
     StringAspect m_taskArgs{this};
@@ -202,7 +202,7 @@ void NimbleTaskStep::setTaskName(const QString &name)
     selectTask(name);
 }
 
-bool NimbleTaskStep::validate()
+bool NimbleTaskStep::init()
 {
     if (m_taskName().isEmpty())
         return true;
@@ -217,8 +217,7 @@ bool NimbleTaskStep::validate()
         emitFaultyConfigurationMessage();
         return false;
     }
-
-    return true;
+    return AbstractProcessStep::init();
 }
 
 // Factory