fix crash on startup under X

since...

commit 240974561685ff44c1abf5157a043d0fde4654d1
Date:   Wed Sep 12 15:12:39 2018 +0200

    loplugin:simplifyconstruct in ucbhelper..vcl

Change-Id: I154893825f5dfa9f2bbc4a0c200df6340e7743cf
diff --git a/vcl/unx/generic/fontmanager/fontmanager.cxx b/vcl/unx/generic/fontmanager/fontmanager.cxx
index ab7c274..336bb81 100644
--- a/vcl/unx/generic/fontmanager/fontmanager.cxx
+++ b/vcl/unx/generic/fontmanager/fontmanager.cxx
@@ -112,7 +112,7 @@ PrintFontManager::PrintFont::PrintFont()
}

GenericUnixSalData::GenericUnixSalData(GenericUnixSalDataType const t, SalInstance *const pInstance)
    : m_eType(t)
    : m_eType(t), m_pDisplay(nullptr)
{
    m_pInstance = pInstance; SetSalData(this);
}