systems/mesa: fix double buffering
systems/mesa: fix double buffering

kevleyski/directfb,DirectFB/directfb,lancebaiyouview/DirectFB,dfbdok/DirectFB1,lancebaiyouview/DirectFB,Distrotech/DirectFB,jcdubois/DirectFB,djbclark/directfb-core-DirectFB,DirectFB/directfb,kevleyski/directfb,kaostao/directfb,mtsekm/test,DirectFB/directfb,lancebaiyouview/DirectFB,Distrotech/DirectFB,lancebaiyouview/DirectFB,dfbdok/DirectFB1,jcdubois/DirectFB,sklnet/DirectFB,dfbdok/DirectFB1,sklnet/DirectFB,djbclark/directfb-core-DirectFB,kevleyski/directfb,sklnet/DirectFB,djbclark/directfb-core-DirectFB,deniskropp/DirectFB,mtsekm/test,mtsekm/test,kevleyski/DirectFB-1,sklnet/DirectFB,kevleyski/DirectFB-1,kaostao/directfb,Distrotech/DirectFB,deniskropp/DirectFB,djbclark/directfb-core-DirectFB,kevleyski/DirectFB-1,kaostao/directfb,deniskropp/DirectFB,jcdubois/DirectFB,kevleyski/DirectFB-1,deniskropp/DirectFB,kevleyski/directfb