coverity#1209003: Unchecked return value

When AcquireGraphics() is true, then it means that we got the graphics
context.

Change-Id: Id5f4a5fc4456f6ce649fdf3ee63ff6103ba65233

vcl/source/outdev/font.cxx

@@ -292,8 +292,11 @@ SystemFontData OutputDevice::GetSysFontData(int nFallbacklevel) const
     SystemFontData aSysFontData;
     aSysFontData.nSize = sizeof(aSysFontData);
 
-    if (!mpGraphics) AcquireGraphics();
-    if (mpGraphics) aSysFontData = mpGraphics->GetSysFontData(nFallbacklevel);
+    if (!mpGraphics)
+    {
+        if (AcquireGraphics())
+            aSysFontData = mpGraphics->GetSysFontData(nFallbacklevel);
+    }
 
     return aSysFontData;
 }