exynos4: removed Android.mk, while building cm-12.0 with mali r3p2

Change-Id: Iea0da9bbd634fc8f57a2d83d0ed4a6e252a7cc16
tmp hack: removed all mk files to fix compiling with old mali setup

Change-Id: I78345b026a0f6df102aff6c48107d094073d6ca1