Call dfb_gfxcard_sync() before FlipRegion() only if hardware has written to the back buffer.
Call dfb_gfxcard_sync() before FlipRegion() only if hardware has written to the back buffer.

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