route: fix breakage after moving lwtunnel state

route: fix breakage after moving lwtunnel state

__recnt and related fields need to be in its own cacheline for performance
reasons. Commit 61adedf3e3f1 ("route: move lwtunnel state to dst_entry")
broke that on 32bit archs, causing BUILD_BUG_ON in dst_hold to be triggered.

This patch fixes the breakage by moving the lwtunnel state to the end of
dst_entry on 32bit archs. Unfortunately, this makes it share the cacheline
with __refcnt and may affect performance, thus further patches may be
needed.

Reported-by: kbuild test robot <[email protected]>
Fixes: 61adedf3e3f1 ("route: move lwtunnel state to dst_entry")
Signed-off-by: Jiri Benc <[email protected]>
Signed-off-by: David S. Miller <[email protected]>