Fix typo in ns-3-click example

src/click/examples/nsclick-wifi-single-interface-promisc.click

@@ -36,7 +36,7 @@ elementclass WiFiSimHost {
 
   // All packets received on eth0 are silently
   // dropped if they are destined for another location
-  FromSimDevice(eth0,4096, PROMISC true)
+  FromSimDevice(eth0,SNAPLEN 4096,PROMISC true)
     -> ToDump(in_eth0.pcap,PER_NODE 1,ENCAP ETHER)
     -> cl;
 
@@ -88,7 +88,7 @@ elementclass TapSimHost {
     -> ToSimDevice($dev,IP);
 
   // Packets sent out by the "kernel" get pushed outside
-  FromSimDevice($dev,4096)
+  FromSimDevice($dev,SNAPLEN 4096)
     -> CheckIPHeader2
     -> ToDump(fromkernel.pcap,2000,IP,PER_NODE 1)
     -> GetIPAddress(16)