directfb-csource: fix colour replacement for transparent pixels
directfb-csource: fix colour replacement for transparent pixels

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