drmkms: allow setting of windows as layer surface
drmkms: allow setting of windows as layer surface

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