Explicitly initialize signing mode

 * Explicitly set signing mode to SelfSigned if not mentioned in the
   .user file
 * Do not use c-style casts.

src/plugins/qt4projectmanager/qt-s60/s60createpackagestep.cpp

@@ -140,7 +140,7 @@ QVariantMap S60CreatePackageStep::toMap() const
 
 bool S60CreatePackageStep::fromMap(const QVariantMap &map)
 {
-    m_signingMode = (SigningMode)map.value(QLatin1String(SIGNMODE_KEY)).toInt();
+    m_signingMode = static_cast<SigningMode>(map.value(QLatin1String(SIGNMODE_KEY), static_cast<int>(SignSelf)).toInt());
     m_customSignaturePath = map.value(QLatin1String(CERTIFICATE_KEY)).toString();
     setCustomKeyPath(map.value(QLatin1String(KEYFILE_KEY)).toString());
     m_createSmartInstaller = map.value(QLatin1String(SMART_INSTALLER_KEY), false).toBool();