Revert "gralloc: Add native support for NV12_LINEAR_FLEX format"

This reverts commit a29bf4ac8b0be78a4ea15146b639e9c361f04d3c.

Bug: 204839811
Bug: 203606132
Change-Id: I7dae52f970bca4ddcf4d9769a6dff604ed2430bc
2 files changed