virtio: fix the gro enable/disable on tx-vrings

Type: fix

Change-Id: I96c30baaf34fe7b0cd899966a507501e58cde934
Signed-off-by: Mohsin Kazmi <sykazmi@cisco.com>
diff --git a/src/vnet/devices/tap/cli.c b/src/vnet/devices/tap/cli.c
index 7580d92..89b2ff0 100644
--- a/src/vnet/devices/tap/cli.c
+++ b/src/vnet/devices/tap/cli.c
@@ -142,7 +142,7 @@
     "[host-ip4-addr <ip4addr/mask>] [host-ip6-addr <ip6-addr>] "
     "[host-ip4-gw <ip4-addr>] [host-ip6-gw <ip6-addr>] "
     "[host-mac-addr <host-mac-address>] [host-if-name <name>] "
-    "[host-mtu-size <size>] [no-gso|gso|csum-offload|gro-coalesce] "
+    "[host-mtu-size <size>] [no-gso|gso [gro-coalesce]|csum-offload] "
     "[persist] [attach] [tun] [packed] [in-order]",
   .function = tap_create_command_fn,
 };