BUG/MEDIUM: peers: register last acked value as origin receiving a resync req

BUG/MEDIUM: peers: register last acked value as origin receiving a resync req

Receiving a resync request, the origins to start the full sync and
to reset after the full resync are mistakenly computed based on
the last update on the table instead of computed based on the
the last update acked by the node requesting the resync.

It could result in disordered or missing updates pushing to the
requester

This patch sets correctly those origins.

This patch should be backported on all supported branches ( >= 1.6 )

(cherry picked from commit 437e48ad9244eaea63881b6c8a86a380c4eecc23)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>