Revert "bpf: Add cookie object to bpf maps"

This reverts commit 963e79f6 which is
commit 12df58ad 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: Ieb4e1d30210d2d01b14077a57e6002679ebbf204
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>