VMware NSX: fix typo

Fix typo in the Neutron VMware NSX driver

Change-Id: I0519e30469c5cfbf285b2ad1032d110f8e9fdbb4
diff --git a/lib/neutron_plugins/vmware_nsx b/lib/neutron_plugins/vmware_nsx
index f2f8735..c7672db 100644
--- a/lib/neutron_plugins/vmware_nsx
+++ b/lib/neutron_plugins/vmware_nsx
@@ -58,7 +58,7 @@
 
 function neutron_plugin_configure_l3_agent {
     # VMware NSX plugin does not run L3 agent
-    die $LINENO "q-l3 should must not be executed with VMware NSX plugin!"
+    die $LINENO "q-l3 should not be executed with VMware NSX plugin!"
 }
 
 function neutron_plugin_configure_plugin_agent {