Revert "bpf: Defer the free of inner map when necessary"

This reverts commit 62fca833 which is
commit 87667336 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: I11fc14db5e679ca1c8ff97dcd96cb2a8fd35122a
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>