iommu/exynos: Remove dead code (set_prefbuf)

exynos_sysmmu_set_prefbuf() is not called any where.

Signed-off-by: Grant Grundler <grundler@chromium.org>
Reviewed-by: Cho KyongHo <pullip.cho@samsung.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
1 file changed