Revert "mm: introduce vma_set_file function v4"

The kernel test robot is not happy with that.

This reverts commit 2b5b95b1.

Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/394773/