tdf#120703 (PVS): redundant nullptr check

V668 There is no sense in testing the 'pCGM' pointer against null, as the
     memory was allocated using the 'new' operator. The exception will be
     generated in the case of memory allocation error.

Change-Id: Ib07d1ceaf01f657e67572c0f5bcd6aae497d2d07
Reviewed-on: https://gerrit.libreoffice.org/62132
Tested-by: Jenkins
Reviewed-by: Mike Kaganski <mike.kaganski@collabora.com>

filter/source/graphicfilter/icgm/cgm.cxx

@@ -695,7 +695,7 @@ ImportCGM(SvStream& rIn, uno::Reference< frame::XModel > const & rXModel, css::u
         try
         {
             std::unique_ptr<CGM> pCGM(new CGM(rXModel));
-            if (pCGM && pCGM->IsValid())
+            if (pCGM->IsValid())
             {
                 rIn.SetEndian(SvStreamEndian::BIG);
                 sal_uInt64 const nInSize = rIn.remainingSize();