selftests: in udpgso_bench do not test udp zerocopy

The udpgso benchmark compares various configurations of UDP and TCP.
Including one that is not upstream, udp zerocopy. This is a leftover
from the earlier RFC patchset.

The test is part of kselftests and run in continuous spinners. Remove
the failing case to make the test start passing.

Fixes: 3a687bef148d ("selftests: udp gso benchmark")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/tools/testing/selftests/net/udpgso_bench.sh b/tools/testing/selftests/net/udpgso_bench.sh
index 792fa4d..850767b 100755
--- a/tools/testing/selftests/net/udpgso_bench.sh
+++ b/tools/testing/selftests/net/udpgso_bench.sh
@@ -35,9 +35,6 @@
 
 	echo "udp gso"
 	run_in_netns ${args} -S
-
-	echo "udp gso zerocopy"
-	run_in_netns ${args} -S -z
 }
 
 run_tcp() {