linux-cp: detect and delete stale entries after sync
linux-cp: detect and delete stale entries after sync

Type: improvement

During synchronization, only the current actual set of entries is
loaded. If some entries are no longer present in the set being loaded
but present in VPP, they should be removed to fully syncronize.

With this change, add handlers for sync begin and end events. Begin
handlers will mark the entries as stale. End handlers will remove the
entries that are still marked as stale.

Signed-off-by: Alexander Chernavin <005bca4307cd9b117df45182181fee477edfa768@netgate.com>
Change-Id: I4f7e872af3e1c9ffa6c63bcc3984ec76def1bb43

chrisy/vpp,chrisy/vpp,FDio/vpp,chrisy/vpp,chrisy/vpp,FDio/vpp,FDio/vpp,chrisy/vpp,chrisy/vpp,chrisy/vpp,FDio/vpp,FDio/vpp,FDio/vpp,FDio/vpp,FDio/vpp,chrisy/vpp