Revert "netfilter: conntrack: allow sctp hearbeat after connection re-use"

This reverts commit 59d2b1e5 which is
commit cc5453a5b7e90c39f713091a7ebc53c1f87d1700 upstream.

It causes ABI breakages and isn't really needed in this tree at this
point in time.

Bug: 161946584
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I05666ad53306b0cfb83e0bac9799e87455c5e16c