[dvs] Mark DPB tests as xfail (sonic-net#1420)

There is a known regression in the VS docker image that is impacting
the DPB tests (buildimage#5263). While this is being fixed, we will
xfail this set of tests so that 1) the PRs are not blocked and 2)
so we can continue to run the tests and verify that the fix is complete.

Signed-off-by: Danny Allen <[email protected]>

Author: daall

tests/test_port_dpb.py

@@ -18,6 +18,7 @@
 maxBreakOut = 4
 
 @pytest.mark.usefixtures('dpb_setup_fixture')
+@pytest.mark.xfail(reason="sonic cfggen bug: buildimage#5263")
 class TestPortDPB(object):
 
     '''

tests/test_port_dpb_acl.py

@@ -9,6 +9,7 @@
 
 
 @pytest.mark.usefixtures('dpb_setup_fixture')
+@pytest.mark.xfail(reason="sonic cfggen bug: buildimage#5263")
 class TestPortDPBAcl(object):
     def test_acl_table_empty_port_list(self, dvs_acl):
         # Create ACL table "test" and bind it to Ethernet0

tests/test_port_dpb_vlan.py

@@ -5,6 +5,7 @@
 
 @pytest.mark.usefixtures('dpb_setup_fixture')
 @pytest.mark.usefixtures('dvs_vlan_manager')
+@pytest.mark.xfail(reason="sonic cfggen bug: buildimage#5263")
 class TestPortDPBVlan(object):
     def check_syslog(self, dvs, marker, log, expected_cnt):
         (exitcode, num) = dvs.runcmd(['sh', '-c', "awk \'/%s/,ENDFILE {print;}\' /var/log/syslog | grep \"%s\" | wc -l" % (marker, log)])