Adding packages configuration.

    Packages can be added in packages/config.mk to indicate a sub-directory
    containing the new package which must have a package.mk file to define build
    targets and add them to the package list.
    At this point, a TI OMAP kernel is built and PVR packages are installed in
    the rootfs. This should provide a working system suitable for GPU
    acceleration with an OMAP4 SoC.