Fixed arguments for NetDll_send.

I was messing with the NetDll functions and I noticed that NetDll_send actually has the same arg0 as the rest of the NetDll functions. 

As an aside I think that arg0 stands for the network that is used, at least that is how it is referenced here: https://github.com/nateleroux/xbdm/blob/master/xbdm/dmnet.h. Should I also make a pull request fixing that as well?