Revert "perf/aux: Fix AUX buffer serialization"

This reverts commit 7882923f which is
commit 2ab9d830 upstream.

It breaks the Android kernel abi and can be brought back in the future
in an abi-safe way if it is really needed.

Bug: 161946584
Change-Id: Iba99f51a8d72daa315077fda4ced39e52200de89
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>