[Buildroot] DirectFB fetch problem (no tarball on the primary mirror)

[Ihar Hrachyshka]

Hello guys!
I have a problem building the image with DirectFB because it can't
fetch the source tarball from the mirror (no such file there). It
seems that DirectFB was updated by upstream from 1.2.6 to 1.2.7 and
then upstream developers removed the source tarball for previous
version from their repo. I think we should update the DirectFB version
to 1.2.7 because it's basically a bug fix release.