Revert "mali: enable vpll mode"
this reverts https://github.com/gustavoss/android_kernel_samsung_smdk4412/commit/18ceac57e81fb77a4868e3a29f08bd034e70293b and https://github.com/gustavoss/android_kernel_samsung_smdk4412/commit/40fbb21ec81f64c5546824db47dae572a55528f6