ipsec: bug fix ipsec-init sequence
ipsec: bug fix ipsec-init sequence

ipsec_tunnel_if_init might be called before ipsec_init
this memset in ipsec-init therefore zero the memory
allocated by ipsec_tunnel_if_init

Change-Id: Ie889f1bf624c76842ef77e5a51ed1d41fed4758d
Signed-off-by: Kingwel Xie <2a62226005ff76ec1b3ca9a6f915ba889ad44cc6@ericsson.com>

FDio/vpp,chrisy/vpp,FDio/vpp,chrisy/vpp,vpp-dev/vpp,chrisy/vpp,chrisy/vpp,vpp-dev/vpp,FDio/vpp,chrisy/vpp,vpp-dev/vpp,FDio/vpp,FDio/vpp,chrisy/vpp,vpp-dev/vpp,chrisy/vpp,vpp-dev/vpp,FDio/vpp,vpp-dev/vpp,vpp-dev/vpp,FDio/vpp,chrisy/vpp,FDio/vpp