Revert "perf/aux: Fix AUX buffer serialization"

This reverts commit 9dc7ad2b 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: Id119523c115b8a3aec08978e22bdb4e894701923
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>