loplugin:fpcomparison in svtools/

Change-Id: I8dc3cc128dc97b429e714c4837dd6cb81fa358d0
Reviewed-on: https://gerrit.libreoffice.org/21862
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Noel Grandin <noelgrandin@gmail.com>

svtools/source/control/ctrlbox.cxx

@@ -372,7 +372,7 @@ static double lcl_getGuessedWidth( long nTested, double nRate, bool bChanging )
         nWidth = double( nTested ) / nRate;
     else
     {
-        if ( double( nTested ) == nRate )
+        if ( rtl::math::approxEqual(double( nTested ), nRate) )
             nWidth = nRate;
     }