buildroot

package/sunxi-mali: remove useless package

sunxi-mali-prop only served a feeding prey for sunxi-mali to get the
proprietary libs.

Now that sunxi-mali downloads them (as the git submodule they are), we
no longer need sunxi-mali-prop.

Remove it.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Peter Korsgaard <peter@korsgaard.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>