Resolves: tdf#122701 opengl settings don't affect gtk3

Change-Id: Iffcf9b6ea8d191a509c2ca451f2ce4a249fde922
Reviewed-on: https://gerrit.libreoffice.org/66292
Tested-by: Jenkins
Reviewed-by: Mike Kaganski <mike.kaganski@collabora.com>

cui/source/options/optgdlg.cxx

@@ -526,7 +526,7 @@ CanvasSettings::CanvasSettings() :
 bool CanvasSettings::IsHardwareAccelerationAvailable() const
 {
 #if HAVE_FEATURE_OPENGL
-    if( OpenGLWrapper::isVCLOpenGLEnabled() )
+    if (OpenGLWrapper::isVCLOpenGLEnabled() && Application::GetToolkitName() != "gtk3")
         mbHWAccelAvailable = false;
 
     else