configure: Allow setting DIRECTFB_VERSION_VENDOR via environment variable.
configure: Allow setting DIRECTFB_VERSION_VENDOR via environment variable.

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