Revert "xfrm: make user policy API complete"

This reverts commit 20fd28df which is
f8d858e6 commit upstream.

It breaks the Android kernel ABI and if this really needs to be added to
Android, it must come back in a format in the future that does not break
the abi.

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I0597156be84f636d8196c81b2625a04bab57dc0c