system-tests: Prevent flakiness in ovn mirroring

The "ovn mirroring" test wasn't waiting for the flows
to be properly installed. That could lead to
smaller number of packets being mirrored thus failing
the test.

Fixes: a88b620 ("mirror: fix ovn mirror support with IPv6")
Signed-off-by: Ales Musil <amusil@redhat.com>
Signed-off-by: Dumitru Ceara <dceara@redhat.com>

tests/system-ovn.at

@@ -11205,6 +11205,9 @@ ovn-nbctl lsp-add bar bar1 \
 ovn-nbctl mirror-add mirror0 gre 1 to-lport 172.16.0.100
 ovn-nbctl lsp-attach-mirror bar1 mirror0
 
+OVN_POPULATE_ARP
+check ovn-nbctl --wait=hv sync
+
 ADD_NAMESPACES(mirror)
 ADD_VETH(mirror, mirror, br-mirror, "2003::b/64", "f0:00:00:01:07:06", \
          "2003::1", "nodad", "172.16.0.100/24", "172.16.0.1")
@@ -11228,7 +11231,8 @@ killall tcpdump
 
 ovn-nbctl mirror-del mirror0
 ovn-nbctl mirror-add mirror1 gre 2 to-lport 2003::b
-ovn-nbctl lsp-attach-mirror bar1 mirror1
+
+ovn-nbctl --wait=hv lsp-attach-mirror bar1 mirror1
 
 NS_CHECK_EXEC([mirror], [tcpdump -l -c 3 -neei mirror proto GRE > gre_mirror6.pcap 2>gre_mirror6_error &])
 OVS_WAIT_UNTIL([grep "listening" gre_mirror6_error])
@@ -11247,7 +11251,7 @@ killall tcpdump
 
 ovn-nbctl mirror-del mirror1
 ovn-nbctl mirror-add mirror2 erspan 3 to-lport 172.16.0.100
-ovn-nbctl lsp-attach-mirror bar1 mirror2
+ovn-nbctl --wait=hv lsp-attach-mirror bar1 mirror2
 
 NS_CHECK_EXEC([mirror], [tcpdump -l -c 3 -neei mirror ip[[22:2]]=0x88be > erspan_mirror4.pcap 2>erspan_mirror4_error &])
 OVS_WAIT_UNTIL([grep "listening" erspan_mirror4_error])
@@ -11265,7 +11269,7 @@ killall tcpdump
 
 ovn-nbctl mirror-del mirror2
 ovn-nbctl mirror-add mirror3 erspan 4 to-lport 2003::b
-ovn-nbctl lsp-attach-mirror bar1 mirror3
+ovn-nbctl --wait=hv lsp-attach-mirror bar1 mirror3
 
 NS_CHECK_EXEC([mirror], [tcpdump -l -c 3 -neei mirror ip6[[42:2]]=0x88be > erspan_mirror6.pcap 2>erspan_mirror6_error &])
 OVS_WAIT_UNTIL([grep "listening" erspan_mirror6_error])
@@ -11282,7 +11286,7 @@ OVS_WAIT_UNTIL([
 killall tcpdump
 
 uuid=$(fetch_column nb:mirror _uuid name="mirror3")
-ovn-nbctl set mirror $uuid type=gre
+ovn-nbctl --wait=hv set mirror $uuid type=gre
 
 NS_CHECK_EXEC([mirror], [tcpdump -c 3 -l -neei mirror proto GRE > gre_mirror6.pcap 2>gre_mirror6_error &])
 OVS_WAIT_UNTIL([grep "listening" gre_mirror6_error])