[GTK] Fix icon rendering issue
[GTK] Fix icon rendering issue

Use the standard RenderIcon method when hi-res icon support is
not available

residuum/xwt,hamekoz/xwt,hwthomas/xwt,directhex/xwt,iainx/xwt,mminns/xwt,akrisiun/xwt,antmicro/xwt,steffenWi/xwt,lytico/xwt,sevoku/xwt,cra0zy/xwt,TheBrainTech/xwt,mono/xwt,mminns/xwt